TS 

2Z7 


9XY-ACETYLENE 
.DING  AND  CUTTING 


BY 


P.  F.  WILLIS 


GIFT  OF 


Mrs.    14  .T 


A 

PRACTICAL  MANUAL 

OF 

OXY-ACETYLENE 
WELDING 

AND 

GUTTING 

WITH  A  TREATISE  ON  ACETYLENE 
AND 


By  P.  F.  WILLIS 


SAINT     LOUIS,     MO.,     U.     S.     A. 


r,  1917 

i    c  i   .     «•        ••       « 

BY  P.   F.  WILLIS 

? 



^.-^llinl 


PREFACE 

Some  ten  years  ago,  the  author  started 
a  welding  shop,  using  the  oxy-acetylene 
process.  He  hardly  knew  how  to  light  the 
torch,  much  less  its  operation.  In  this 
respect  he  was  on  an  equal  footing  with 
a  few  other  venturesome  individuals  in 
this  country  who  had  embarked  in  the  same 
business,  regarding  which  practically  noth- 
ing was  known.  It  follows  that  there  were 
many  failures  and  disappointments. 

The  author  can  well  testify  that  "  there 
is  no  royal  road  to  learning,"  and  yet  in 
offering  this  treatise  he  is  prompted  by 
the  belief  that  the  man  who  goes  ahead 
may  smooth  out  some  of  the  rough  spots, 
and  thereby  assist  those  who  come  after. 
The  book  is  sold  at  a  price  which  precludes 
the  possibility  of  profit  to  the  author.  You 
pay  only  for  the  printing  and  the  paper  — 
the  subject-matter  is  gratis.  Do  not  look 
a  gift  horse  in  the  mouth  too  closely. 

P.  F.  WILLIS. 
St.  Louis,  Mo., 
January,  1917. 


468997 


CONTENTS 

CHAPTER  I. 
ACETYLENE. 

History  of.  Generation.  Hazard.  Cost.  Compressed 
or  Dissolved.  Market  Price.  Disadvantages  of 
Compressed  and  Generated  Gas.  Properties.  .7-26 

CHAPTER  II. 
OXYGEN. 

Properties.  Various  Methods  of  Manufacture  with 
Description  of  each.  Effect  of  Temperature  on 
Compressed  Gas.  How  to  Determine  Contents  of 
Cylinder  under  Pressure  with  Table  for  same. 
Effect  of  Impurities  in  Gas 27-42 

CHAPTER  III. 
WELDING   AND   CUTTING   TORCH. 

Requisites  for  Welding  Torch.  Difficulties  in 
Manufacture.  Plash-backs.  Waste  of  Oxygen. 
Different  Types  of  Torches.  Opinions  of  Author- 
ities. Chemical  Changes  Taking  Place  in  Oxy- 
acetylene  Flame.  Objections  to  Some  Torches. 
Operation  of  Cutting  Torch.  Theoretical  Amount 
of  Oxygen  Necessary  for  Cutting.  Effect  on  the 
Steel  43-63 

CHAPTER  IV. 
APPARATUS  AND  INSTALLATION. 

Regulators.  Construction  and  Care.  Gauges. 
Goggles.  Acetylene  Generator.  Important  Con- 
siderations. Portable  Generators.  Directions 
for  Connecting  up  Tank  and  Generator  Plant.  .64-83 


CONTENTS. 


CHAPTER  V. 

PREPARING    FOR    WELDING. 

Tools  Necessary  for  Repair  Welding.  Cleaning  the 
Metal.  Beveling.  Pre-heating  Methods  and  De- 
vices. Expansion  and  Contraction.  Melting 
Points  of  Metals.  Regulation  of  Flame.  Exe- 
cution of  a  Weld 84-102 

CHAPTER  VI. 
WELDING  OF  DIFFERENT  METALS. 

Welding  of  Cast-iron,  Steel,  Brass  or  Bronze,  Cop- 
per, Aluminum,  Malleable  Iron,  and  Lead  Burn- 
ing   103-120 

CHAPTER  VII. 
WELDING    OF    SHEET    METAL   AND   PIPE. 

Sheet  Metal  Welding.  Various  Kinds  of  Welds. 
Machine  Welding  of  Sheet  Metal.  Welding  of 
Gas,  Ammonia,  Air,  Steam  and  Water  Pipes. 
Tests  and  Costs  of  Same.  Illustrations  of 
Work 121-139 

CHAPTER  VIII 
WELDING  OF  VARIOUS  PIECES. 

Welding  of  Boilers,  Automobile  Cylinder,  Lug  on 
Manifold,  Scored  Cylinder,  Arm  on  Aluminum 
Crank  Case,  Crack  in  Aluminum  Oil  Pan,  Fly- 
wheel, Large  Cylinders,  Crank  Shaft,  Partitions 
in  Oil  Tank  Wagons,  Dies,  High  Carbon  to  Low 
Carbon  Steel,  Manganese  Steel,  Use  of  Aluminum 
Solder,  Oxygen  for  Removing  Carbon.  Cost-Card. 
Receipt  Ticket.  Description  of  Welded  Castings. 
Useful  Information 1 40-1 80 


OXY-ACETYLENE   WELDING 
AND  GUTTING. 

CHAPTER  I. 

ACETYLENE. 

What  is  Acetylene? 

A  hydro  carbon  gas  composed  of  equal 
volumes    of    carbon    and    hydrogen.      By 
weight  it  is  composed  of  93%  carbon  and 
7%  hydrogen. 
When  was  it  discovered? 

In  1836  by  Davy,  an  English  chemist, 
and  Berzelius,  a  Swiss  chemist. 
From  what  is  Acetylene  obtained? 

From  calcium  carbide. 
What  is  Calcium  Carbide? 

It  is  a  substance,  hard  like  rock,  of  a 
grayish  color,  and  possessing  a  slight  crys- 
talline structure. 
When  ivas  it  discovered? 

In  1892  by  an  American  chemist,  named 
Willson,  at 'Spray,  N.  C. 
How  is  it  manufactured? 

Lime  and  coke  in  the  proportion  of  56 
parts  by  weight  of  the  former  to  36  parts 
of  the  latter  are  fused  or  melted  together 
in  an  electric  furnace.  It  is  cooled  and 


8      ;  pilY-AC^Tyi^E^^  vVELDING  &  CUTTING. 


,  and;  i:  :then  assorted  as  to  size 
by  iiieaiig  of  screens. 


How  is  Acetylene  obtained  from  Calcium 

Carbide? 
When   calcium   carbide   and  water   are 

brought  together,  acetylene  is  formed.  This 

is  accomplished  as  follows: 

The  calcium  in  the  calcium  carbide 
combines  with  some  of  the  oxygen  in  the 
water  and  forms  first  calcium  oxide 
or  quick  lime,  and  then  calcium  hydroxide 
(slacked  lime).  The  carbon  in  the  calci- 
um carbide  combines  with  some  hydro- 
gen from  the  water  to  form  acetylene, 
the  chemical  symbol  of  which  is  C2  H2. 

Is  there  more  than  one  method  of  bringing 

the  Carbide  and  water  together® 
Yes,  there  are  three  methods. 

Name  them. 

First,  water  to  carbide;  second,  reces- 
sion ;  third,  carbide  to  water. 

Explain  each  method. 

The  "water  to  carbide"  method  consists 
in  allowing  water,  drop  by  drop,  to  fall 
upon  a  body  of  carbide.  This  was  the 
earliest  method  of  generating  acetylene 
and  its  adoption  was  due  to  the  fact  that 
it  was  easier  to  control  the  flow  of  water 
than  it  was  the  feeding  of  the  carbide; 


ACETYLENE. 

especially  as  the  carbide  first  put  on  the 
market  was  not  uniform  as  to  size. 

The  "recession"  method  consists  in  al- 
lowing water  to  rise,  coming  in  contact  with 
either  a  mass  of  carbide  or  successive  lay- 
ers of  carbide. 

The  "carbide  to  water"  method  consists 
in  feeding  the  carbide  in  small  amounts 
into  a  large  volume  of  water. 

Which  is  the  best? 

The  "carbide  to  water." 

*rr  -  ~     !•'.'•    "•-•;''  •*' 

Why? 

After  generation  is  impossible  and  purer 
gas  is  produced.  Again  when  carbide  and 
water  are  brought  together  heat  is  evolved. 

Now  this  heat  can  be  considerable,  some- 
times reaching  1000°  F.,  or  it  can  be  negli- 
gible, depending  entirely  upon  the  amount 
of  water.  If  there  is  a  sufficient  amount 
of  water  both  the  carbide  and  the  water 
will  be  kept  cool.  It  has  been  found  that 
if  for  each  pound  of  carbide,  one  gallon 
of  water  is  supplied,  the  temperature  is 
kept  down — in  fact,  cannot  possibly  exceed 
212°  F.,  and  in  practice  never  goes  that 
high.  The  "carbide  to  water"  method  is 
the  only  one  that  guarantees  a  sufficient 
amount  of  water  to  assure  cool  generation. 


10       OXY-ACETYLENE  WELDING  &  CUTTING. 

What  effect  does  heat  have  on  Acetylene 
during  generation® 

If  the  heat  should  rise  high  enough,  what 
chemists  term  polymerization  takes  place. 
By  this  is  meant  that  the  acetylene  under- 
goes a  change  and  is  transformed  into 
other  gases,  such  as  benzol,  styrolene,  etc. 
These  latter  gases  require  for  their  com- 
bustion a  different  amount  of  oxygen  than 
does  acetylene,  and  their  flame  temperature 
is  not  so  high. 

A  temperature  that  would  produce  pol- 
ymerization, would  also  be  hazardous,  and 
if  there  was  any  mixture  of  air  with  the 
gas,  an  explosion  would  likely  result. 
Is  it  possible  Jo  explode  Acetylene? 

Yes. 
How? 

First,  when  mixed  with  air  in  the  proper 
proportions — 3%  to  58%  of  acetylene  to 
the  rest  air — and  in  the  presence  of  a  spark 
or  flame. 

Second,  at  a  pressure  of  24  pounds  it  is 
possible  for  it  to  explode  without  any  air 
mixture,  in  the  presence  of  spark  or  flame. 

Third,  when  compressed  in  an  ordinary 
container  to  30  pounds  or  more  it  may  ex- 
plode without  any  air  mixture  and  without 
a  spark  or  flame.  Neither  concussion  or 
shock  are  necessary  to  produce  the  explo- 
sion. An  explosion  of  this  character  is 


ACETYLENE.  11 

generally  attributed  to  decomposition, 
although  some  claim  that  it  is  due  to  im- 
purities in  the  carbide,  such  as  sulphur  and 
phosphorus  forming  combinations  which 
ignite  spontaneously. 

Is  it  possible  to  compress  Acetylene  to  25 

pounds  or  higher  safely? 
Yes. 

Howf 

The  container  is  first  filled  with  a  porous 
substance,  such  as  asbestos  cement.  It  is 
then  further  filled  with  an  inflammable 
liquid  called  acetone.  This  liquid,  acetone, 
has  been  found  to  possess  the  peculiar 
quality  of  dissolving  or  absorbing  25  times 
its  volume  of  acetylene  at  atmospheric 
pressure  and  continues  to  do  this  for  each 
atmosphere  of  pressure  (15  pounds)  it  is 
put  under. 

While  the  asbestos  cement  apparently 
fills  the  tank,  in  reality,  on  account  of  its 
porosity,  only  20%  of  the  space  in  the  tank 
is  occupied  by  the  asbestos;  acetone  to  the 
amount  of  about  43%  of  the  capacity  of 
the  tank  is  then  added.  This  leaves  about 
37%  of  the  contents  of  the  tank  for  acety- 
lene as  it  is  taken  up  or  dissolved  by  the 
acetone.  This  absorbing  or  dissolving  qual- 
ity of  the  acetone  is  so  remarkable  that 
it  may  be  well  to  compare  the  amount  of 


12       OXY-ACETYLENE  WELDING  &  CUTTING. 

acetylene  that  a  tank  of  one  cubic  foot 
capacity  would  contain  under  fifteen  at- 
mospheres (225  pounds)  and  the  amount 
the  same  size  tank  will  contain  under  the 
same  pressure  but  with  the  gas  dissolved. 
In  the  first  instance  there  will  be  approxi- 


Fig.  1. 
Commercial  Acetylene  Co.'s  Tank. 

mately  fifteen  cubic  feet  of  gas.    We  sim- 
ply multiply  the  cubic  contents  (one  foot) 
by  the  number  of  atmospheres  (fifteen). 
In  the  latter,  however,  there  will  be  about 


ACETYLENE.  13 

161  cubic  feet  or  roughly  estimated  at 
about  ten  times  as  much  gas  as  in  the  first 
tank.  This  is  obtained  as  follows: 

The  amount  of  acetone  is  about  43%  of 
the  contents  of  the  tank  whose  capacity 
was  assumed  to  be  one  cubic  foot.  There- 
fore, the  acetone  occupies  .43  of  a  cubic 
foot.  At  atmospheric  pressure  the  acety- 
lene dissolves  twenty-five  times  its  volume 
of  acetylene,  so  that  in  this  case  at  zero 
gauge  pressure  there  is  in  the  tank  .43x25 
or  10.75  cubic  feet  of  acetylene  and  at  225 
pounds  pressure  there  will  be  10.75x15  or 
161  cubic  feet. 

Docs  Acetylene  exercise  a  toxic  action  if 
air  containing  a  large  proportion  of  it 
is  breathed? 

The  best  authorities  agree  that  acetylene 
itself  possesses  very  small  poisonous  qual- 
ities, so  that  the  danger  of  breathing  it  is 
practically  nil.  This  is  because  it  is  almost 
free  of  carbon  monoxide. 

Hoiv  much  Acetylene  will  a  pound  of  car- 
bide produce  when  made  ivith  a  gen- 
erator? 

Conservatively  4^2  cubic  feet  for  the 
lump  size  and  4^  cubic  feet  for  the  very 
small  size.  One  carbide  manufacturer 
claims  five  cubic  feet  and  another  4.8  cubic 
feet,  but  their  figures  cannot  be  obtained. 


14       OXY-ACETYLENE  WELDING  &  CUTTING. 

What  is  the  present  price  of  carbide? 

Three  and  three-fourth  cents  per  pound 
without  a  contract ;  from  S1^  to  S^c  per 
pound  with  a  contract,  according  to  con- 
sumption. 

What  is  the  cost  of  Acetylene  per  cubic 
foot  made  from  a  generator  at  above 
prices  for  carbide? 

Not  to  exceed  8/10  of  a  cent  per  cubic 
foot  or  80c  per  100  cubic  feet. 
What  is  the  price  of    dissolved    or    com- 
pressed Acetylene? 

From  $1.80  per  100  cubic  feet  to  large 
users  to  $2.15  per  100  cubic  feet  to  the 
average  consumer  plus  freight  on  the  full 
tank  and  on  the  empty  tank  returned. 
Taking  into  consideration  the  freight,  what 
is    the    average    cost    of    "tanked" 
Acetylene? 
Two  and  one-half  cents  per  cubic  foot. 

What  size  or  capacity  of  Acetylene  tank 

should  be  used  for  welding® 
Under  no  circumstances  should  a  tank 
of  less  capacity  than  100  cubic  feet  be  used. 
A  tank  should  not  be  discharged  at  a  faster 
rate  than  one-seventh  of  its  capacity  per 
hour.  This  means  that  a  welding  tip  should 
not  be  used  on  a  100-cubic  foot  tank  if  it 
consumes  more  than  15  cubic  feet  per  hour. 
The  use  of  small  automobile  tanks  should 


ACETYLENE.  15 

be  discouraged,  only  the  very  lightest  work 
can  be  done  and  the  cost  of  the  gas  is  con- 
siderably more  than  it  is  when  using  the 
regular  welding  cylinder. 
When    would    you    advise     the    use     of 

"tanked"  Acetylene? 
When  only  occasional  welding  or  cutting 
is  done  or  where  portability  is  desired. 
When  would  you  advise  the  use  of  a  gen- 
erator^ 

When  stationary  welding  or  cutting  is 
done,  using  about  200  cubic  feet  of  acety- 
lene or  more  per  week. 
What  is  the  saving  over  tanked  Acetylene 

per  100  cubic  feet? 

The  difference  between  80c  for  generator 
gas  and  $2.50  for  tanked  gas,  or  $1.70. 
Has  the  tanked  gas  any  disadvantages? 

Yes. 
Name  them. 

(1)  Inconvenience  and  delay  in  shipping 
tanks. 

(2)  No  assurance  that  you  receive  full 
amount  of  gas  in  tank. 

(3)  Some   gas   always   remains   in   the 
tank. 

(4)  The   solvent    (acetone)    mixes   with 
the  acetylene  and  produces  a  bad  weld. 

(5)  Certain  make  of  tank  not  your  prop- 
erty. 


16       OXY-ACETYLENE  WELDING  &  CUTTING. 

(6)  Likelihood    of    leakage    from    tank 
greater  than  from  generator  on  account  of 
higher  pressure. 

(7)  Lack  of  sufficient  gas  to  finish  a  job. 

(8)  Hazard. 

Explain  each  of  the  above. 

INCONVENIENCE    AND    DELAY    IN 
SHIPPING   TANKS. 

The  inconvenience  and  delay  incident  to 
shipping  tanked  acetylene  is  a  serious 
problem.  Delays  in  shipment  will  neces- 
sarily occur,  and  they  usually  occur  when 
the  welding  plant  is  most  needed.  But, 
with  the  very  best  possible  time,  it  is  usu- 
ally two  or  three  days  before  a  full  tank  is 
received.  One  of  the  important  values  of 
a  welding  plant  is  readiness  to  serve.  Any- 
one familiar  with  custom  welding  realizes 
that  75%  of  the  repair  work  must  be  gotten 
out  in  a  hurry.  It  is  rush  work,  and  your 
value  to  the  customer  increases  when  you 
are  in  a  position  to  at  all  times  take  care 
of  the  work  promptly. 

NO     ASSURANCE     THAT     YOU     RECEIVE     FULL 
AMOUNT   OF   GAS   IN   TANK. 

With  tanked  acetylene  you  must  depend 
upon  the  correctness  of  the  companies  re- 
charging the  cylinders.  A  gauge  on  the 
tank  will  only  indicate  the  pressure  of  the 
gas — not  the  quantity  of  gas.  No  one  but 


<^ 


ACETYLENE.  17 

the  recharging  people  can  tell  how  much 
gas  is  in  a  cylinder  as  the  amount  of  gas 
depends  not  only  upon  the  size  of  tank  and 
the  pressure,  but  also  upon  the  quantity 
and  quality  of  the  solvent — 'acetone — in  the 
tank.  It  takes  a  smart  man  that  can  look 
through  a  steel  tank  and  tell  how  much 
acetone  is  on  the  inside,  and  there  is  no 
way  for  the  customer  to  measure  it.  No 
one  questions  the  honesty' of  any  of  the 
firms  engaged  in  the  filling  of  acetylene 
tanks,  but  their  employees  are  human ;  they 
are  likely  to  make  mistakes;  and  as  a 
matter  of  fact  they  do  sometimes  make 
mistakes. 

SOME    GAS    ALWAYS    REMAINS    IN    THE    TANK. 

With  tanked  gas  you  never  get  all  the 
gas  out  of  the  tank.  A  quite  considerable 
amount  of  gas  remains  and  is  shipped  back 
to  the  recharging  station  to  be  resold  to  you 
in  your  next  tank. 

THE  SOLVENT  (ACETONE)  MIXES  WITH  THE 

ACETYLENE  AND  PRODUCES' 

A  BAD  WELD. 

When  tanked  acetylene  is  used,  the  gas 
from  a  full  tank  will  produce  an  excellent 
weld,  but  as  the  pressure  and  the  amount 
of  gas  in  the  tank  is  lowered,  the  acetone 
or  solvent  comes  off  also,  adulterating  the 
acetylene,  contaminating  it  with  a  hydro- 


18       OXY-ACETYLENE  WELDING  &  CUTTING. 

carbon  of  less  heat  units  and  consequently 
lowering  the  temperature  of  the  flame.  This 
acetone  also  contains  impurities  which  af- 
fect the  strength  of  the  weld.  That  the 
acetone  is  carried  off  and  burned  with  the 
acetylene  is  evidenced  by  the  fact  that  one 
of  the  refilling  companies  at  one  time  made 
a  charge  of  2c  per  ounce  for  whatever  loss 
of  acetone  was  shown  when  the  tank  was 
returned. 

A  CERTAIN  MAKE  OF  TANK  NOT  YOUR 
PROPERTY. 

Acetylene  tanks  are  simply  loaned  by  one 
of  the  different  concerns  compressing 
acetylene  under  a  "Service  Agreement," 
for  which  they  charge,  and  you  are  com- 
pelled by  the  agreement  to  get  your  re- 
charges from  them.  You  do  not  own  the 
tank.  It  is  not  even  leased  to  you.  You 
simply  pay  a  certain  amount  for  the  privi- 
lege of  buying  their  gas  and  you  cannot  go 
into  the  open  market  and  buy  your  acety- 
lene. 

LIKELIHOOD       OF       LEAKAGE       FROM       TANK 

GREATER    THAN    FROM    GENERATOR    ON 

ACCOUNT  OF  HIGH  PRESSURE. 

The  pressure  of  the  gas  in  the  high  pres- 
sure generator  cannot  exceed  15  pounds. 
The  pressure  of  the  gas  in  an  acetylene 
tank  is  at  least  225  pounds,  and  maybe 
more.  It  must  be  obvious  that  the  likeli- 


ACETYLENE.  19 

hood  of  leakage  is  greater  under  the  higher 
pressure. 

LACK   OF   SUFFICIENT   GAS    TO   FINISH   A   JOB. 

It  often  occurs  that  a  welding  job  comes 
in  which  will  take  a  fair  amount  of  gas. 
Perhaps  a  part  of  the  gas  in  your  tank  has 
been  used  on  other  work  and  not  enough 
remains  to  do  this  particular  job.  What 
are  you  going  to  do!  You  can  use  what 
gas  is  in  the  tank  to  partially  weld  the  cast- 
ing, then  send  your  empty  tank  in  and 
write  or  wire  for  another  full  one.  This 
means  that  the  casting  cools  down  and  you 
have  lost  your  heat,  which  cost  money ;  be- 
sides, distortion  often  occurs  on  account 
of  this  cooling  when  only  partially  welded. 
You  could  send  the  partially  full  tank  back 
at  once  and  order  a  full  tank,  but  this 
means  loss  of  gas  in  the  tank  returned. 

HAZARD. 

Any  power-producing  agency  has  inher- 
ent hazards,  and  acetylene  is  no  exception. 
A  generator  of  good  design  and  workman- 
ship possesses  no  greater  hazards  than  a 
compressed  or  dissolved  acetylene  tank. 
Some  tanks  have  exploded;  so  have  some 
generators ;  so  that  any  claims  to  the  con- 
trary, it  is  a  stand-off  between  the  two  on 
the  question  of  hazard. 


20      OXY-ACETYLENE  WELDING  &  CUTTING. 

What  are  the  disadvantages  of  a  gen- 
erator? 

First,  there  is  a  slight  variance  in  pres- 
sure of  the  gas  between  locking  and  releas- 
ing the  motor.  This  necessitates  occasional 
adjustment  of  the  flame  by  means  of  the 
torch  cocks.  This  is  largely  overcome  by 
means  of  a  special  regulator. 

Second,  recharging  the  generator  and  re- 
moval of  sludge  requires  about  twenty 
minutes.  The  indolent  may  offer  this  as 
an  objection. 

Third,  cost  of  generator  is  much  more 
than  cost  of  a  tank. 

Fourth,  some  precautions  must  be  taken 
to  prevent  freezing  in  winter. 

Fifth,  generators  should  not  be  moved 
when  filled  with  carbide,  and  used  for  port- 
able work. 

Sixth,  generator  house  should  be  pro- 
vided, which  necessitates  an  expense. 

What  fuel  gas  is  best  adapted  for  welding? 

Acetylene. 
Why? 

The  temperature  of  an  acetylene  flame 
when  burned  with  oxygen  is  in  excess  of 
6300°  F.  This  is  a  temperature  exceeding 
by  over  2000°  F.  its  nearest  rival,  hydro- 
gen. It  is  the  flame  temperature  that 


ACETYLENE.  21 

counts  in  welding  and  not  the  B.  T.  U.  's  of 


What  are  some  of  the  gases  that  have  at 
various  times  tried  to  compete  with 
Acetylene? 

Hydrogen,  Blau  gas,  Wolf  gas,  thermo- 
lene,  oxy-carbo,  etc. 

What  are  the  objections  to  the  above? 

First,  it  is  impossible  to  do  heavy  weld- 
ing unless  these  gases  are  enriched  with 
acetylene. 

Second,  usually,  the  cost  of  doing  such 
work  as  is  practical,  is  more  than  it  would 
cost  using  actylene  when  all  factors,  such 
as  labor,  are  considered. 

Why  does  Acetylene,  when  burned  with 
oxygen,  give  us  the  hottest  fuel  flame 
knownf 

Broadly  speaking,  the  gas  which  has  the 
greatest  amount  of  carbon  and  the  least 
amount  of  hydrogen  will  give  us  the  hot- 
test flame.  Acetylene  contains  by  weight 
93%  carbon,  almost  approaching  gaseous 
carbon.  There  is  another  property  which 
acetylene  possesses,  which  assists  in  in- 
creasing the  flame  temperature  and  it  is 
the  fact  that  it  is  an  endothermic  com- 
pound. 


22       OXY-ACETYLENE  WELDING  &  CUTTING. 

What  is  meant  by  an  Endo thermic  Com- 
pound? 

It  is  a  compound  whose  formation  from 
elementary  substances  is  attended  with  ab- 
sorption of  heat.  The  electric  furnace  has 
made  the  manufacture  of  carbide  practicable. 
Authorities  differ  as  to  whether  calcium 
carbide,  when  formed,  absorbs  or  liberates 
heat,  but  they  are  agreed  that  when  car- 
bide and  water  are  brought  together  slacked 
lime  and  acetylene  are  formed  and  that  the 
former  liberates  heat,  while  the  acetylene 
absorbs  heat.  When  the  acetylene  is 
burned,  this  absorbed  'or  stored-up  heat  is 
liberated,  and  helps  to  increase  the  flame 
temperature. 

What  is  it  that  limits  the  temperature  of 
the  Oxy-Acetylene  flame? 

The  dissociation  point  of  carbon  mon- 
oxide—(C.O.). 

What  is  meant  by  the  dissociation  point 
of  an  inflammable  gas? 

It  is  the  temperature  at  which  the  gas  re- 
fuses to  unite  with  oxygen. 
At  what  pressure  does  Acetylene  liquefy? 

At  26  Atmospheres   (2821bs.) — At  32  Degrees  F. 
At  40  Atmospheres   (588  Ibs.)—  At  70  Degrees  F. 

What  is  Cppper  Acetylide? 

It  is  a  compound  which  is  formed  when 
acetylene   is   exposed    for   a    considerable 
V  time  to  copper. 


ACETYLENE.  23 

/  What  properties,  if  any,  does  this  com- 


pound possess? 
^  Iti 


is  explosive. 

What  lesson  do  we  learn  from  this? 

That  under  110  condition  should  copper 
be  used  when  it  will  come  in  contact  with 
acetylene. 

What  is  the  density  or  specific  gravity  of 

Acetylene? 

Assuming  air  to  be  unity  or  1,  it  is  .91 
for  acetylene.  It  is  therefore  slightly 
lighter  than  air. 

Does  Acetylene,  ivhen  burned,  give  off  any 

Ultra  Violet  Rays? 

It  does  not,  so  that  no  harm  can  come  to 
the  eyes  from  this  score.  However,  it  must 
be  remembered  that  any  bright  light  will 
in  time  tire  and  weaken  the  eyes  so  that 
it  is  strongly  recommended  that  smoked 
glasses  be  worn. 

What  is  the  weight  of  a  cubic  foot  of  Acety- 
lene? 
.069  of  a  pound. 

How  many  cubic  feet  of  Acetylene  does  it 

take  to  weigh  a  pound? 
14.5  cubic  feet. 

What  is  the  ignition  temperature  of  a  mix- 

liire  of  Acetylene  and  air? 
About  805  °F, 


24       OXY-ACETYLENE  WELDING  &  CUTTING. 

What  concerns  manufacture  Carbide? 
American  Carbolite  Company. 
Canadian  Carbide  Company. 
Union  Carbide  Company. 

What     companies     furnish     compressed 

Acetylene? 

Commercial  Acetylene  Welding  Com- 
pany. 

Prest-0-Lite  Company. 

Searchlight  Company. 

What  is  the  policy  of  each  company  ivith 
reference  to  furnishing  the  gas? 

The  Commercial  Acetylene  Company  sel- 
dom sell  any  of  their  tanks.  They  usually 
loan  them  to  responsible  people  without 
charge.  They  furnish  tanks  having  a  ca- 
pacity of  125  cubic  feet,  250  cubic  feet  and 
500  cubic  feet. 

The  Prest-0-Lite  Company  manufac- 
tures two  sizes  of  tanks,  one  of  which  con- 
tains practically  100  cubic  feet  of  gas  and 
the  other  300  cubic  feet.  They  charge  un- 
der a  service  agreement  $20.00  for  the  small 
size,  and  $40.00  for  the  large  size  tank. 

The  Searchlight  people  charge  $30.00  for 
the  small  tank,  and  $60.00  for  the  large 
tank. 

Each  of  these  companies  will  refill  only 
their  own  tanks. 


ACETYLENE.  25 

Which  compressed  Acetylene  companies  of- 
fer the  best  proposition  to  the  user? 

The  Commercial  Company  is  the  only 
one  of  the  three  who  furnish  the  tanks  free. 

The  reader  can  judge  for  himself  as  to 
whether  he  would  prefer  to  pay  for  the 
tanks  or  simply  have  them  loaned.  It  must 
be  remembered  that  service  is  a  very  im- 
portant consideration,  and  in  some  cases 
it  is  advisable  to  purchase  the  tanks  in 
order  to  get  prompt  delivery. 

Are  there  any  hazards  in  connection  with 

Acetylene? 

There  are  some  who  believe  in  minimiz- 
ing the  hazards  in  connection  with  acety- 
lene. The  writer  does  not  belong  to  that 
school.  Any  sensible  man  realizes  that  any 
power-producing  agency,  whether  it  be 
steam,  electricity,  gasoline  or  acetylene 
holds  within  itself  possibilities  for  good  or 
evil.  It  would  seem  that  one  way  of  avoid- 
ing accidents  with  acetylene  is  to  apprise 
and  thoroughly  familiarize  one's  self  with 
its  properties.  When  properly  handled, 
acetylene  will  unite  in  a  molten  mass,  a  6x6 
inch  iron  beam,  and  the  same  power  which 
accomplishes  this  wonder  of  yesterday  will 
play  havoc  if  one  becomes  careless  and  re- 
fuses to  follow  a  very  few  simple  and  com- 
mon sense  rules.  Millions  upon  millions 


26       OXY-ACETYLENE  WELDING  &  CUTTING. 

of  feet  of  acetylene,  both  tanked  and  gen- 
erated, are  used  yearly  with  but  a  trifling 
number  of  accidents  as  compared  with  the 
installations. 

A  few  acetylene  tanks  and  generators 
have  exploded.  Where  the  explosion  oc- 
curred inside  the  generator,  it  was  seldom 
of  a  serious  character.  Where  considerable 
damage  results  it  is  usually  caused  by  the 
gas  leaking  out  in  considerable  quantities 
in  the  room  from  the  tank  or  the  generator 
and  mixing  with  the  air.  Never  under  any 
circumstances  try  to  find  a  leak  with  a 
lighted  match.  Elsewhere  we  will  advise 
more  fully  as  to  the  care  that  should  be 
observed  when  working  with  acetylene. 


CHAPTER  II. 

OXYGEN. 

What  is  Oxygen? 

Oxygen  is  an  element.  It  is  the  most 
abundant  and  most  widely  distributed  of 
all  the  elements,  constituting  by  weight 
more  than  one-fifth  the  air,  and  eighth- 
ninths  of  all  the  water  on  the  globe.  It 
enters  largely  into  the  solid  constituents  of 
the  earth's  crust,  and  is  found  "in  the  tis- 
sues and  fluids  of  all  forms  of  animal  and 
vegetable  life. 

Oxygen  is  a  colorless,  tasteless  gas  and 
is  essential  to  the  support  of  all  animal 
life. 

What  is  the  density  or  specific  gravity  of 
Oxygen? 

Assuming  air  to  be  unity  or  1,  it  is  1.105 
for  oxygen.  It  is,  therefore,  slightly 
heavier  than  air. 

How  many  cubic  feet  of  Oxygen  does  it 
take  to  make  a  pound? 

11.209  cubic  feet. 
What  does  a  cubic  foot  of  Oxygen  iveigh? 

.08921  of  a  pound  or  100  cubic  feet 
weighs  8.92  pounds. 

What  are  some  of  the  various  methods  of 
making  or  procuring  Oxygen? 

(1)     Red  oxide  of  mercury. 

-      27 


28      OXY-ACETYLENE  WELDING  &  CUTTING. 

(2)  Sodium  peroxide. 

(3)  Chlorate  process,  with  either  po- 
tassium chlorate  or  sodium  chlorate. 

(4)  Erin's  process  or  the  use  of  barium 
oxide. 

(5)  Lavoisite  process. 

(6)  Electrolysis  of  water. 

(7)  Liquid  Air. 

Describe  each? 

Oxygen  can  be  obtained  by  heating  red 
oxide  of  mercury.  This  is  purely  a  lab- 
oratory experiment,  not  being  commercial- 
ly practical.  Its  only  interest  lies  in  the 
fact  that  this  method  was  the  first  one  em- 
ployed to  produce  oxygen. 

SODIUM   PEROXIDE    PROCESS. 

Sodium  peroxide  is  a  yellow  solid  which 
when  brought  in  contact  with  water  liber- 
ates oxygen.  This  process  is  extremely 
simple.  Each  pound  of  sodium  peroxide 
will  produce  two  cubic  feet  of  oxygen  of 
high  purity.  The  market  price  of  the  chem- 
ical is  high  so  that  the  cost  of  oxygen  by 
this  method  is  excessive,  ranging  from 
about  12  to  20  cents  per  cubic  foot.  This 
method  is  employed  to  some  extent  in  pro- 
curing oxygen  for  medicinal  purposes, 
used  mainly  in  conjunction  with  nitrous 
oxide  (laughing  gas)  as  an  anaesthetic. 


OXYGEN.  29 

CHLORATE  PROCESS. 

Potassium  chlorate  when  heated  alone 
to  a  temperature  of  about  350°  F.  gives 
off  oxygen.  It  has  been  found  that  if  man- 
ganese dioxide  is  mixed  with  the  potas- 
sium chlorate  in  the  proportion  of  about 
100  pounds  of  potassium  chlorate  to  14 
pounds  of  the  manganese  that  it  does  not 
require  so  much  heat  to  liberate  the  oxy- 
gen— only  about  200°  F.,  so  that  in  prac- 
tice this  is  usually  done.  If  sodium  chlor- 
ate is  used,  the  amount  of  manganese  is 
increased  somewhat.  Potassium  chlorate 
will  give  off  about  five  cubic  feet  of  oxygen 
per  pound  and  the  sodium  chlorate  will 
produce  about  12%  more  oxygen  per 
pound.  Sodium  chlorate  is  not  so  stable 
a  compound  as  potassium  chlorate,  and 
the  latter  chemical  was  in  much  greater 
favor  than  the  former. 

At  the  prevailing  prices  of  these  chemi- 
cals before  the  European  War,  the  gas 
could  be  made  for  about  2  cents  per  cubic 
foot,  and  of  a  purity  ranging  from  85%  to 
98%,  depending  entirely  upon  the  method 
and  care  exercised  in  purifying. 

There  were  two  methods  of  making  oxy- 
gen by  this  process.  One  consisted  in  gen- 
erating the  gas  under  its  own  pressure  and 
was  designated  by  the  trade  as  a  "Self- 
Compressing  ' '  type.  The  gas  made  by  this 


rfU       OXY-ACETYLENE  WELDING  &  CUTTING. 

method  was  of  low  purity  and  was  at- 
tended by  hazards  of  so  serious  a  character 
that  the  better  class  of  manufacturers  tried 
to  discourage  its  use.  The  other  method 
consisted  of  heating  the  chemicals  in  a 
sealed  retort,  allowing  the  gas  to  pass 
through  several  scrubbers  and  purifiers, 
collecting  in  a  gas  holder  and  then  com- 
pressing into  tanks.  The  present  price  of 
chemicals  makes  this  method  impractical. 

ERIN'S  PROCESS 

or 
BARIUM    OXIDE    PROCESS. 

In  this  method  of  making  oxygen,  barium 
oxide  is  used  and  the  gas  is  produced  by 
the  alternate  formation  of  barium  dioxide 
and  its  decomposition  into  barium  oxide. 
The  installation  of  a  plant  requires  con- 
siderable space  and  special  heating  require- 
ments are  necessary  so  as  to  produce  a 
working  temperature  of  800°  F.  The  proc- 
ess consists  in  heating  barium  oxide  and 
directing  upon  it  a  blast  of  air,  when  it 
takes  up  oxygen  from  the  air  and  forms 
barium  dioxide  (Ba02).  The  tempera- 
ture is  then  raised  and  the  barium  dioxide 
decomposes  into  barium  oxide  and  oxygen. 
The  process  is  theoretically  simple,  but  in 
practice  presents  certain  serious  difficul- 
ties. At  one  time  several  of  these  plants 
were  operating  in  this  country,  but  they 


OXYGEN.  Ol 

were  not  a  commercial  success  and  were 
abandoned. 

LAYOISITE    PROCESS. 

This  is  a  trade  name,  lavoisite  being  a 
chlorine  product.  The  process  consists  in 
bringing  together  the  chemical  and  water 
that  has  been  heated  to  about  180°  P.,  when 
oxygen  is  evolved.  One  pound  of  lavoisite 
and  one-half  pound  of  water  will  produce 
one  cubic  foot  of  oxygen  of  excellent  pur- 
ity. The  cost  is  about  the  same  as  the 
chlorate  process. 

ELECTROLYSIS    OF   WATER   PROCESS. 

Oxygen  and  hydrogen  are  liberated  when 
a  suitable  electric  current  is  passed 
through  water  whose  conductivity  has  been 
increased  by  the  addition  of  either  an  acid 
or  an  alkali.  From  the  positive  pole  will 
pass  oxygen  and  from  the  negative  pole 
will  pass  hydrogen.  There  will  be  generated 
2  cubic  feet  of  hydrogen  for  each  1  cubic 
foot  of  oxygen.  The  vessel  in  which  the 
electrolytic  action  takes  place  is  called  a 
cell.  This  cell  is  divided  or  separated  into 
two  chambers  by  means  of  a  partition — 
usually  of  pure  asbestos  cloth.  The  object 
of  this  partition  is  to  keep  the  two  gases- 
hydrogen  and  oxygen — from  mixing,  so 
that  it  is  of  the  highest  importance  that 
these  asbestos  diaphragms  or  partitions 
be  of  the  very  best  of  material  in  order  that 


32      OXY-ACETYLENE  WELDING  &  CUTTING. 

the  danger  from  rupture  shall  be  mini- 
mized. Should  the  hydrogen  and  the  oxygen 
be  allowed  to  mix,  it  would  be  attended  by 
very  grave  danger,  as  even  so  low  a  mix- 
ture as  5%  hydrogen  and  the  remainder 
of  oxygen  or  vice  versa  will  explode. 

Oxygen  made  by  this  process  is  usually 
of  an  excellent  quality;  gas  98%  pure 
should  be  obtained  direct  from  the  cells 
and  if  purified  will  be  in  excess  of  99% 
pure. 

Various  types  of  cells  are  offered  the 
public.  The  claims  of  the  manufacturers 
as  to  the  efficiency  range  anywhere  from  3 
to  3.8  cubic  feet  of  oxygen  and  twice  that 
amount  of  hydrogen  per  kilowatt  hour. 
Probably  3^2  cubic  feet  of  oxygen  would  be 
a  conservative  figure.  Assuming  that  an 
electric  current  rate  of  one  cent  per  K. 
W.  H.  was  obtained,  100  cubic  feet  of  oxy- 
gen would  cost  28  cents.  To  this  must  be 
added  interest  on  investment,  deprecia- 
tion, labor,  overhead  and  cost  of  compress- 
ing into  tanks.  This  is  on  the  assumption 
that  the  hydrogen  is  not  marketable.  How- 
ever, in  recent  years  there  has  been  created 
a  quite  considerable  demand  on  the  part  of 
soap  and  cottonseed  lard  manufacturers 
for  hydrogen,  for  what  is  known  as  "oil- 
hardening."  Where  the  hydrogen  can  be 
utilized,  this  effects  a  very  material  saving 


OXYGEN.  33 

in  the  cost  of  the  oxygen  and  under  these 
conditions  the  electrolytic  process  will  be 
a  strong  competitor  with  any  process.  A 
number  of  industrial  concerns  throughout 
the  country  have  installed  small  electro- 
lytic plants,  primarily  to  obtain  hydrogen. 
This  gives  them  as  a  by-product  a  very 
limited  amount  of  oxygen  and  some  are  at- 
tempting to  market  it.  We  would  strongly 
advise  against  the  use  of  this  gas  and  un- 
hesitatingly recommend  that  the  customer 
purchase  oxygen  only  from  those  concerns 
who  are  engaged  primarily  in  the  oxygen 
business,  for  the  reason  that  the  concern 
whose  principal  business  is  the  manufac- 
ture and  sale  of  oxygen  is  not  only  much 
more  apt  to  appreciate  the  necessity  for 
pure  gas,  but  as  his  reputation  is  at  stake 
will  undoubtedly  more  frequently  test  his 
gas  for  impurities  than  the  concern  who 
is  in  the  business  merely  as  a  side-issue. 

LIQUID   AIR   PROCESS. 

Obtaining  oxygen  by  the  liquid  air 
method  is  a  refrigeration  process.  By 
compressing  the  air  and  then  allowing 
it  to  expand  through  a  small  opening 
a  temperature  sufficiently  low  to  liquefy, 
the  air  is  obtained.  This  tempera- 
ture is  374°  below  zero  F.  at  atmospheric 
pressure — a  temperature  so  cold  that  it  is 
almost  impossible  to  realize  it.  The  nitro- 


34       OXY-ACETYLENE  WELDING  &  CUTTING. 

gen  is  allowed  to  evaporate,  leaving  liquid 
oxygen  behind.  The  liquid  oxygen  is  in 
turn  allowed  to  gasify  and  is  led  to  suitable 
gas  holders,  from  which  it  is  compressed 
into  steel  drums  or  tanks.  The  perfection 
of  this  process  is  due  very  largely  to  the 
efforts  of  Linde,  Claude  and  Hildebrandt. 

It  is  possible  to  obtain  oxygen  of  a  high 
purity  by  this  process.  About  20%  is  added 
to  the  manufacturing  cost  by  increasing 
the  purity  from  92%  to  97%,  and  further 
increasing  the  purity  to  99%  entails  an  ad- 
ditional 10%  to  the  manufacturing  cost. 
From  this  it  will  be  readily  seen  that  there 
is  always  the  temptation  during  exceed- 
ingly busy  times  to  decrease  the  purity  of 
the  gas.  The  impurity  in  liquid  air  oxygen 
is  nitrogen,  an  inert  gas.  The  cost  of  oxy- 
gen by  this  process  depends  upon  the  size 
of  the  installation  and  whether  the  plant 
is  operated  continuously.  Claude,  in  his 
work  on  Liquid  Air,  Oxygen  and  Nitrogen, 
states  that  oxygen  can  be  made  "for  2 
centimes  the  cubic  meter."  A  centime  is 
equivalent  to  one-fifth  of  a  cent  and  a  cubic 
meter  is  equal  to  35.3  cubic  feet,  so  that 
•this  amount  of  gas  would  cost  two-fifths  of 
a  cent,  or  100  cubic  feet  of  gas  would  cost 
one  and  one-fifth  cents.  If  these  figures 
are  correct,  he  did  not  take  into  consid- 
eration, depreciation,  labor,  overhead,  etc. 


OXYGEN.  35 

What  is  the  present  market  price  of  Oxy 

gen? 

From-lVi  cents  per  cubic  foot,  to  very 
large  users,  to  2  cents  per  cubic  foot  tt) 
small  users. 

In  irhdt  land  of  containers  is  Oxygen  fur- 
nished? 

In  steel  drums  in  which  the  gas  is  com- 
pressed to  about  1800  pounds. 
When  a  gas  is  compressed  to  so  high  a 
pressure,  is  there  not  danger  of  leak- 
age at  the  tank  valve? 
Yes.     The   purchaser   should   insist   on 
valves  that  will  open  and  close  easily  and 
which  will  not  leak  around  or  through  the 
packing  gland  regardless  as  to  the  position 
of  the  valve  stem. 

What  is  the  policy  of  the  various  Oxygen 
Companies  with  reference  to  furnish- 
ing the  steel  drums? 
To  responsible  parties  they  will  furnish 
the  tanks  free  for  a  period  of  30  days,  but 
they    retain   the   right   to   make    a   rental 
charge  of  a  small  amount  for  the  tank  if 
it  is  not  returned  within  the  30  days. 
What    capacity    tanks    are    usually    fur- 
nished? 

100  cubic  feet,  150  cubic  feet,  200  cubic 
feet  and  250  cubic  feet. 
Does  the  temperature  of  the  air  affect  the 
pressure  in  the  tank"    Yes. 


36       OXY-ACETYLENE  WELDING  &  CUTTING. 

Ho  iv? 

As  the  temperature  increases  the  pres- 
sure of  the  gas  in  the  tank  increases  on  ac- 
count of  it  expanding  and  as  the  tempera- 
ture decreases,  the  pressure  drops. 

Give  table  showing  the  different  pressures 
at  various  temperatures? 

Table  of  pressures  per  degree  for  tanks  carrying 
1800-lbs.  at  68  degrees  P.  Pressure  in  pounds  per 
degree  at  any  temperature  from  zero  "P."  to  100 
degrees  above  zero  "P."  inclusive,  with  the  volume 
remaining  constant  at  all  times. 


Temp. 

T>eg. 

tr1 

Press. 
Lb. 
Per, 
Des. 

Temp. 

I>eg. 
F. 

Press. 
Lb. 
Per. 
Deg. 

Temp. 

Degi 

F- 

Press. 
Lb. 
Per. 
Dcg. 

Temp. 

Deg. 
F. 

Press. 
Lb. 
Per. 
Deg. 

0   !  150X      20 

10-57 

51 

1743      76     1828 

i    irr,2    27 

1060 

52 

1746 

77     1831 

•2     1575   i    28 

1(564 

53 

1749 

78     1835 

3     1  r>79 

-   29 

1667 

54 

1753 

79 

1838 

4     1582 

30 

1071 

55 

1756 

80 

1842 

6 

1585 

31 

1074 

56 

1760 

81 

1845 

6 

1589 

32 

1678 

57 

1763 

82 

1848 

7 

1592 

33 

1681 

58 

1766 

83 

1852 

8 

1590 

34 

1684 

59 

1770 

84 

1855 

9 

1599 

35 

1088 

60 

1773 

85 

1859 

10 

1603 

36 

1691 

61 

1777 

86 

1862 

11 

1006 

37 

1695 

62 

1780 

87 

1865 

12 

1609 

38 

1698 

63 

1784 

88 

1869 

13 

1613 

39 

1701 

64 

1787 

89 

1872 

14 

1610 

40 

1705 

65 

1790 

'90 

1876 

15 

1020 

41 

1708 

60 

1794 

91 

1879 

16 

1623 

42 

1712 

07 

1797 

92 

1883 

17 

1626 

43 

1715 

68 

1800 

93 

1886 

18 

1630 

44 

1719 

69 

1803     94 

1889 

19 

1633  i    45 

1722 

70 

1807      95 

1893 

20 

16-37      46 

1725 

71 

1811      96     1895 

21 

1040  i    47 

1729 

72 

1814  !    97     1900 

22   i  1043 

48 

1732 

73 

1818      98     1903 

23   i  1647 

49 

1730 

74 

1821      99     1906 

24     1650 

50 

1739 

75 

1824  j   100     1910 

25 

1654 

1 

Of  what  value  is  this  table? 

If  the  temperature  to  which  the  tank  has 


OXYGEN.  37 

been  exposed  is  known,  by  referring  to  the 
column  adjoining,  there  is  shown  the  pres- 
sure that  the  tank  should  be  under  if  it  is 
what  is  known  as  a  "full"  tank.  As  an 
example,  suppose  the  temperature  was  32° 
F.,  and  the  tank  had  been  exposed  to  this 
temperature  sufficiently  long  for  the  gas 
to  be  cooled  to  the  same  point,  then  the 
pressure  on  the  gauge  would  indicate  1678 
pounds.  On  the  other  hand,  assume  that 
it  was  summer  and  the  temperature  97°  F. 
Then  the  pressure  should  be  1900  pounds. 
In  both  cases  there  was  the  same  amount 
of  gas  in  each  tank,  but  the  pressures  dif- 
fered, due  solely  to  the  gas  in  the  latter 
case  expanding  and  in  the  former  con- 
tracting as  the  temperature  varied. 

We  see  from  the  table  above  that  tempera- 
ture affects  the  pressure  of  gas.  Is 
there  any  fixed  rule  for  determining 
this? 

It  has  been  found  that  for  every  change 
in  temperature  of  one  degree  Fahrenheit 
there  is  a  corresponding  change  in  volume 
which  amounts  to  1/491  of  the  original  vol- 
ume of  the  gas.  If  a  gas  occupying  one 
cubic  foot  of  space  under  a  temperature  of 
say,  70°  F.  would  be  raised  to  a  tempera- 
ture of  71°  F.,  the  volume  would  be  in- 


38       OXY-ACETYLENE  WELDING  &  CUTTING. 

creased  1/491  of  one  cubic  foot.  For  each 
change  in  temperature  of  one  degree  Fah- 
renheit there  is  a  corresponding  change  in 
pressure  of  approximately  3.42  pounds. 

What  does  this  suggest? 

That  some  certain  degree  of  tempera- 
ture should  arbitrarily  be  chosen  as  a 
standard  from  which  to  measure  oxygen. 

Has  this  been  done? 

Yes.  Most  oxygen  companies  have  taken 
70°  F.,  some  68°*  F. 

How  do  you  determine  the  contents  of  a 
cylinder  under  pressure? 

It  is  first  necessary  to  know  the  contents 
of  the  cylinder  at  atmospheric  pressure. 
This  is  determined  by  multiplying  the  area 
of  the  head  by  the  length  of  the  cylinder. 
The  area  of  the  head  is  obtained  by  multi- 
plying the  square  of  the  diameter  by  .7854. 
Thus  a  cylinder  having  a  diameter  of  2  feet 
and  a  length  of  3  feet  will  have  a  cubical 
contents  of— .7854x(2x2)x3  or  9.4248  cubic 
feet.  After  the  cubic  contents  have  been 
found  it  is  only  necessary  to  multiply  this 
by  the  pressure  in  atmospheres  to  find  the 
cubic  contents  under  any  pressure. 

What  is  an  atmosphere? 

It  is  the  pressure  of  the  air  at  sea  level 
and  has  been  definitely  determined  to  be 


OXYGEN.  oKJ 

14.7  pounds,  but  for  rough  calculation  15 
pounds  is  generally  used. 

//  a  cylinder  lias  a  cubic  contents  of  one 
cubic  foot  at  atmospheric  pressure 
(zero  gauge  pressure),  what  would  be 
the  cubic  contents  at  1800-pound  pres- 
sure? 

The  1800-pound  pressure  is  reduced  to 
atmospheres  by  dividing  by  15  pounds  or 
one  atmosphere.  The  1800  pounds  is 
found  to  be  equivalent  to  120  atmospheres. 
The  cubic  contents  of  the  cylinder — 1  cubic 
foot — is  then  multiplied  by  120,  the  number 
of  atmospheres  of  pressure  and  a  product 
of  120  cubic  feet  is  obtained.  In  other 
words,  there  is  enough  gas  in  this  tank 
which  is  under  1800  pounds  pressure  to 
fill  a  tank  of  120  cubic  feet  capacity  under 
only  ordinary  atmospheric  pressure. 

In  practice  liow  is  the  amount  of  Oxygen 

in  a  tank  determined? 

Most  manufacturers  of  apparatus  have  a 
gauge  marked  on  the  dial  to  read  both  in 
pounds  pressure  and  in  cubic  feet. 

It  may  be  of  interest  to  some  to  know  the 
amount  of  gas  in  the  different  size  of  oxy- 
gen cylinders  under  varying  pressures.  We 
accordingly  give  a  table  herewith  for  tanks 
holding  100,  150  and  200  cubic  feet  of  gas 
under  1750  pounds  pressure. 


Press  in  Lbs 

.  100  cu.  ft. 

150  cu.  ft. 

200  cu.  ft. 

per 

Tank 

Tank 

Tank 

Sq.  In. 

Cu.  Ft. 

Cu.  Ft. 

Cu.  Ft. 

15 

.855 

1.282 

1.710 

30 

1.710 

2.565 

3.420 

45 

2.565 

3.84 

5.120 

60 

3.42 

5.13 

6.84 

75 

4.275 

6.4 

8.55 

90 

5.13 

7.69 

10.26 

105 

5.985 

8.97 

11.97 

120 

6.84 

10.26 

13.68 

135 

7.695 

11.53 

15.39 

150 

8.55 

12.82 

17.1 

200 

11.4 

17.1 

22.8 

250 

14.25 

21.37 

28.5 

300 

17.10 

25.65 

34.2 

350 

19.95 

29.92 

39.9 

400 

22.8 

34.2 

45.6 

450 

25.65 

38.47 

51.3 

500 

28.5 

42.7 

57. 

550 

31.65 

47.47 

63.3 

600 

34.50 

51.7 

69. 

650 

37.35 

56. 

74.7 

700 

40.2 

60.3 

80.4 

750 

43.05 

64.57 

86.1 

800 

45.09 

68.8 

91.8 

850 

48.75 

73.12 

97.5 

900 

51.6 

77.4 

103.2 

950 

54.45 

81.67 

108.9 

1000 

57.5 

86.2 

115. 

1050 

60.35 

90.52 

120.7 

1100 

63.2 

94.8 

126.4 

1150 

66.05 

99. 

132.1 

1200 

68.9 

103.3 

137.8 

1250 

71.75 

107.6 

143.5 

1300 

74.60 

111.9 

149.2 

1350 

77.45 

116.17 

154.9 

1400 

80.20 

120.3 

160.4 

1450 

83.05 

124.5 

166.1 

1500 

85.9 

128.8 

171.8 

1550 

88.75 

133.12 

177.5 

1600 

91.5 

137.2 

183. 

*  1650 

94.35 

141.5 

188.7 

1700 

97.2 

145.8 

194.4 

1750 

100.05 

150. 

200.1 

OXYGEN. 


41 


Does  the  purity  of  Oxygen  have  any  in- 
fluence on  welding  or  cutting? 

Any  impurity  in  the  oxygen  will  lower 
its  efficiency.  This  is  not  so  noticeable  in 
welding  if  the  impurity  is  not  in  excess  of 
2%  or  3%,  but  in  cutting  it  is  claimed  that 
even  a  \%  impurity  is  apparent  not  only 
as  to  the  time  and  the  quantity  of  oxygen 
necessary  to  do  the  work,  but  also  the  ap- 
pearance of  the  cut. 

Some  years  ago,  Mr.  J.  M.  Morehead  in 
a  paper  read  before  the  International 
Acetylene  Association,  presented  the  re- 
sults of  test  on  the  cutting  power  of  oxy- 
gen of  varying  purity.  His  table  follows : 

METAL  CUT  MILD  STEEL  PLATE  %"  THICK. 


K 

p 

0! 

•o 
a 
8 

•  o 

£    W 

1 

K 

0| 

V 

e 

e 

2 

0 
o 

o 

1 

ft 

S-i    Q 

|1 

f-l 

0^ 

Appearance   of   Cut 

a 

C 

fij 

9) 

s 

11 

jl 

E?  °- 

ai 

If 

H 

£ 

H£ 

^ 

H  3 

Ho 

0^ 

^g 

^0 

1      99.3 

67%     272 

7.5 

48 

1  .  3    Taken  asUnit 

Very  good 

2 

98. 

67%     285  !    9.1  i      51      1.6       23%         6%  |  Good  cut 

a 

97.6 

67%  i  295 

9.8 

52      1.7      31%         8%  1  Fair  cut 

4 

96.8 

68%  i  363 

11.8 

64      2.         54% 

33%     Fair  cut 

5 

96.4 

67%     360 

11.3 

64      2.1       61% 

33% 

Ragged  and  cindery 

6 

95. 

67  %     377 

11.6        67 

2.         61% 

39% 

Ragged,  dirty  and  cindery 

7 

92. 

67  V2     551 

16. 

98 

2.7     108%  ;  104% 

Very  dirty  and  rough 

8 

87.3    67% 

660 

16.2 

117 

2.9    123%     114%  i  Blew  back  badly,  very  rough 

9 

83.3 

67%     855 

18.9 

153      3.4    154%  !  214%  i    Very  rough  and  ragged,  not 

properly  cut 

Subsequent   to   the   publication   of  this 
table,  the  writer  experimented  along  the 


42       OXY-ACETYLENE  WELDING  &  CUTTING. 

same  lines.  While  we  were  never  able  to 
show  so  marked  a  difference  in  the  cutting 
power  between  pure  oxygen  and  that  of 
lesser  purity  as  indicated  by  Mr.  Morehead, 
still  the  difference  was  such  as  to  justify 
us  in  recommending  that  users  of  oxygen 
insist  upon  being  furnished  oxygen  of  a 
high  degree  of  purity. 


CHAPTER  III. 

WELDING  AND  CUTTING  TORCH. 

THE  OXY-ACETYLENE  WELDING  TORCH. 
What  are  the  requisites  for  a  good  welding 
torch? 

The  oxy-acetylene  welding  torch  should 
be  simple  of  design,  light,  yet  sufficiently 
strong  in  its  construction  and  provide  for 
the  bringing  together  of  oxygen  and  acety- 
lene and  mixing  these  gases  in  the  correct 
proportions. 


Fig.    2. 
An     Oxy- Acetylene    AY  elding     Torch. 

Of  u'hat  does  a  welding  torch  consist? 

It  consists  of  a  handle  through  which 
pass  two  conduits  or  tubes,  one  of  which  is 
for  the  acetylene  and  the  other  for  the 
oxygen.  These  tubes  are  each  provided 
with  cocks  or  valves  and  they  in  turn  are 
connected  to  the  hose  which  carry  the  gases 
from  their  source  of  supply.  The  other 

43 


44       OXY-ACETYLENE  WELDING  &  CUTTING. 

ends  of  the  two  tubes  are  firmly  connected 
with  what  is  known  as  the-  torch  head.  It 
is  either  here  or  in  the  tip  itself  that  the 
mixture  is  accomplished.  Tips  of  various 
sizes  are  usually  furnished. 

In  the  manufacture  of  a  torch  what  have 
been    the    chief    difficulties    to    over- 
come? 
First,  the  tendency  to  " flash-back,"  and 

second,  a  waste  of  oxygen. 

What  produces  a  "flash-back"? 

Primarily  it  is  produced  by  allowing  the 
velocity  or  speed  of  the  mixed  gases  (acety- 
lene and  oxygen)  to  drop  below  the  speed 
of  propagation  of  the  flame.  This  occurs 
when  the  pressure  in  the  acetylene  gener- 
ator or  tank  becomes  low.  This  may  oc- 
cur by  reason  of  the  partial  obstruction  of 
pipes  or  openings  in  the  torch  or  tips. 

What  is  meant  by  "the  velocity  of  propa- 
gation of  the  flame"? 

The  speed  with  which  a  mixture  of  acety- 
lene and  oxygen  will  travel  when  ignited. 
Row  fast  does  a  mixture  of  Acetylene  and 
Oxygen  travel  when  lighted? 

About  330  feet  per  second. 
What  do  we  learn  from  this? 

That  the  two  gases  when  mixed  should 
be  under  a  pressure  sufficient  to  insure  a 
speed  of  over  330  feet  per  second  when 


FLASH-BACKS.  45 

the  mixture   escapes   from  the   nozzle   of 

the  tip. 

How  does  tills  prevent  a  "flash-back"? 

If  the  gases  passing  out  of  the  tip  are 
traveling  at  a  speed  of,  say,  350  feet  per 
second,  then  if  the  flame  can  only  travel 
330  feet  per  second,  it  follows  that  the 
flame  cannot  pass  into  the  torch.  The  un- 
ignited  gases  traveling  faster  will  always 
push  the  flame  away  from  the  tip. 

What  is  meant  l>y  a  "waste  of  Oxygen"  in 

a  torch? 

Two  and  one-half  volumes  of  oxygen 
are  required  to  completely  consume  one 
volume  of  acetylene.  Theoretically  one 
and  one-half  volumes  of  oxygen  can  be 
taken  from  the  air  and  one  volume  from 
the  tanked  gas.  So  much  for  theory.  It 
is  almost  an  axiom  that  one  never  obtains 
in  practice  what  they  should  in  theory.  The 
oxy-acetylene  torch  is  no  exception.  In- 
stead of  one  cubic  foot  of  tanked  oxygen 
being  consumed  for  each  one  cubic  foot 
of  acetylene,  in  practice  the  best  torches 
use  from  10  to  15%  more  oxygen  than 
acetylene  and  any  increase  in  this  amount 
means  among  other  things  a  waste  of  oxy- 
gen. 

Hotv  are  welding  torches  classified? 

According  to  the  pressure  of  the  acety- 
lene. 


4()       OXY-ACETYLtENE  WELDING  &  CUTTING. 

Row  many  and  what  are  tltese  classes  in 

this  country? 
There  are  two: 

1st  — Those     using     low     pressure 

acetylene  and 

2nd — Those    using    what    is    called 
high  pressure  acetylene. 

What  is  meant  by  Loiv  and  High  Pressure 
Acetylene® 

The  terms  are  simply  comparative. 
"Low  pressure''  torches  are  those  de- 
signed primarily  to  use  acetylene  from  a 
generator  or  gas-holder  in  which  the  pres- 
sure is  about  three  inches  of  water  column 
or  practically  two  ounces. 

"High  pressure"  torches  are  those  de- 
signed to  use  acetylene  at  a  pressure  of 
from  one  pound  in  the  smallest  tips  to 
as  high  as  ten  pounds  in  the  largest  tips. 
The  acetylene  is  taken  either  from  a  tank 
in  which  the  gas  is  compressed  or  from  a 
special  pressure  acetylene  generator.  It 
will  be  seen  that  the  highest  pressure  used 
—ten  pounds — is  really  not  a  high  pres- 
sure except  as  compared  with  the  "low 
pressure "  torch  using  about  two  ounces. 
There  has  been  some  objection  to  the  use 
of  the  term  "high  pressure"  for  fear  that 
the  public  might  construe  "high"  pres- 
sure to  possibly  mean  a  dangerous  pres- 
sure, and  some  have  preferred  to  use  the 


LOW   PRESSURE    TORCH.  47 

term  ' ' medium ' '  pressure.  The  terms  high 
pressure  and  medium  pressure  as  used  in 
this  country  are  synonymous.  There  is  no 
more  danger  working  under  ten  pounds 
pressure  than  there  is  under  two  ounces. 

How  is  a  loiv  pressure  torch  constructed? 
The  acetylene  under  a  few  ounces  of 
pressure  flows  into  a  compartment 
through  which  the  oxygen  is  passing  at  a 
high  velocity.  The  high  speed  of  the  oxy- 
gen draws  or  sucks  in  the  acetylene.  This 
is  what  is  known  as  the  injector  principle. 

How    is    the    high    pressure    torch    con- 
structed? 

Both  the  acetylene  and  oxygen  are  un- 
der a  few  pounds  pressure.  These  gases 
flow  through  openings  accurately  de- 
termined into  a  mixing  chamber  from 
which  they  are  conveyed  to  the  nozzle. 

Which  type  of  torch  is  considered  the  best? 
The  high  pressure. 

Why? 

Because  numerous  tests  have  proven 
that  in  practice,  the  high  pressure  torch 
of  good  design  using  the  acetylene  under 
a  few  pounds  pressure  consumes  practical- 
ly equal  quantities  of  acetylene  and  oxy- 
gen, whereas  the  low  pressure  torch  re- 
quires an  excess  of  oxygen  ranging  from 
10%  to  30%  more  than  high  pressure 


48      OXY-ACETYLENE  WELDING  &  CUTTING. 

torches,  depending  upon  the  size  of  the 
tip.  In  a  series  of  experiments  conducted 
by  the  Engineering  Experiment  Station 
of  the  University  of  Illinois  the  propor- 
tion of  acetylene  at  normal  regulation  aver- 
aged 42%  in  the  low  pressure  torch.  This 
is  a  ratio  of  1.38  volumes  of  oxygen  to  one 
of  acetylene.  A  good  high  pressure  torch 
will  not  use  nearly  so  much  oxygen. 

Are  there  any  authorities  whose  tests  prove 

the  above  assertion? 
Yes. 

Name  a  few  of  them  and  state  briefly  what 
they  have  to  say? 

' '  For  blow  pipes  of  high  pressure  all  the 
experiments  agree  in  showing  that  the  re- 
spective volumes  of  gas  used  are  prac- 
tically equal,  and  this  is  obtained  in  prac- 
tice if  the  operators  are  competent." 

"The  blow  pipes  for  low  pressure  acety- 
lene are  those  with  which  the  most  difficulty 
has  been  obtained  even  in  approaching  the 
theoretical  equal  volumes." 

GBANJON  &  ROSEMBERG. 

"In  the  high  pressure  type  the  adjust- 
ment of  the  flame  is  far  easier  with  both 
gases  under  pressure ;  once  the  adjustment 
is  made  right  it  remains  so ;  a  more  inti- 
mate mixing  of  the  gases  is  obtained  than 
in  the  low  pressure  type,  and  this  secures 


AUTHORITIES.  49 

higher  efficiency.  This  is  of  considerable 
importance,  as  it  is  found  that  with  high 
pressure  blow  pipes  considerably  less 
acetylene  and  oxygen  is  required  to  do  a 
fixed  quantity  of  work  than  is  necessary 
with  the  low  pressure  blow  pipe." 

L.  A.  (TROTH. 

"In  the  high  pressure  type  torch,  both 
gases  being  under  pressure  maintain  quite 
accurately  their  relative  proportions  when 
once  properly  adjusted.  In  the  injector  or 
low  pressure  torch,  each  change  of  tem- 
perature of  the  blow  pipe  or  of  the  tip 
forming  the  outlet  causes  some  variation 
in  the  size  of  the  opening  and  consequently 
variations  in  the  relative  proportions  of 
the  issuing  gases." 

WHITTEMORE. 

"The  low  pressure  torch  is  defective  in 
that  it  very  often  does  not  carry  enough 
acetylene  through  it  to  neutralize  the  ef- 
fect of  the  oxygen,  consequently  the  weld 
is  oxidized." 

RICHARD  HART. 

"All  burners  or  torches  with  oxygen 
under  pressure  and  acetylene  without  pres- 
sure, i.  e.,  injector  type,  become  after  a 
short  time  of  working  practically  useless." 

"The  radiating  heat  affects  the  oxygen 
which  is-  under  pressure,  with  great  veloc- 


DU       OXY-ACETYLENE  WELDING  &  CUTTING. 

ity  in  a  narrow  space  in  a  different  way 
than  its  action  upon  the  acetylene  con- 
tained in  a  larger  space  and  without  pres- 
sure. ?  ? 

"The  result  is  a  decomposition  of  the 
flame  and  a  burning  of  the  metal. ' ' 

"This  can  only  be  prevented  by  a  skillful 
welder. ' ' 

DR.  A.  HILPERT,  Berlin. 

In  the  low  pressure  torch,  the  acety- 
lene is  drawn  into  the  tip  by  the  suction 
of  the  oxygen  operating  by  a  device  known 
as  the  Giffard  Injector.  In  the  injector 
type  of  torch  the  amount  of  acetylene 
dratvn  in,  varies  as  the  square  of  the  oxy- 


What  chemical  changes  take  place    when 

Oxygen  and  Acetylene  are  Imrned? 
It  may  be  well  to  state  that  all  combus- 
tion, with  the  exception  of  some  unimpor- 
tant laboratory  experiments,  is  the  result 
of  combining  carbon  with  oxygen,  hydro- 
gen with  oxygen,  or  combinations  of  hydro- 
gen and  carbon,  called  hydro-carbons,  with 
oxygen.  As  stated  before,  acetylene  is  a 
hydro-carbon.  That  is,  it  contains  both 
hydrogen  and  carbon.  The  layman  when 
watching  the  phenomenon  of  combustion 
is  apt  to  consider  its  action  as  destroying 
something.  Such  is  not  the  case.  It  is 


CHEMICAL    CHANGE.  51 

simply  a  chemical  change  and  invariably 
combustion  finally  produces  carbonic  acid 
gas  or  carbon  dioxide  (C(X)  and  water  or 
water  vapor  (H20).  In  order  to  properly 
explain  the  change  or  reaction  that  takes 
place  it  becomes  necessary  to  use  symbols, 
but  in  this  case  they  are  simple  and  Ave 
feel  sure  they  will  be  easily  understood. 

It  may  be  advisable  to  state  here  some 
of  the  symbols  which  we  will  use,  together 
with  what  they  stand  for. 

H  is  the  symbol  for  hydrogen. 

C  is  the  symbol  for  carbon. 

0  is  the  symbol  for  oxygen. 
CO  is  the  symbol  for  carbon  monoxide. 
COo  is  the  symbol  for  carbon  dioxide   or 
carbonic  acid  gas. 

H.,0  is  the  symbol  for  water  or  water  va- 
por. 

C,H2  is  the  symbol  for  acetylene. 

Acetylene  (C2H2),  as  previously  stated, 
is  composed  of  equal  parts  of  hydrogen  and 
carbon  and  it  unites  with  an  equal  volume 
of  oxygen  (02)  to  form  the  first  reaction. 
This  reaction  is  indicated  by  the  following 
equation : 

(a)     a,H,+(X=2  CO+H, 
In  other  words,  1  molecule,  which  is  the 


5Z      OXY-ACETYLENE  WELDING  &  CUTTING. 

technical  expression  for  a  unit  volume  of 
acetylene,  unites  with  1  molecule  of  oxygen. 
A  unit  volume  of  oxygen  is  expressed  as 
02  and  is  made  up  of  two  parts  or  atoms 
of  oxygen. 

The  primary  stages  of  combustion  as  in- 
dicated in  equation  (a)  result  as  indicated 
in  production  of  2  unit  volumes  of  carbon 
monoxide  (2  CO)  and  1  unit  volume  of 
hydrogen  (H2)  which,  like  oxygen,  is  made 
up  of  two  parts  or  atoms.  Now  these  prod- 
ucts of  the  primary  stage  of  combustion 
are  formed  in  the  small,  bluish-white  cone 
of  the  flame.  This  is  shown  in  Fig.  3. 


This  cone  is  the  zone  of  greatest  heat  in 
the  flame.  The  secondary  or  final  stage  of 
combustion  takes  place  in  the  outer  flame 
which  not  only  surrounds  the  small  white 
cone,  but  extends  for  quite  a  considerable 
distance  beyond  it.  In  this  outer  flame, 
the  carbon  monoxide  (2  CO)  and  the  hydro- 
gen (H2)  which  were  shown  to  have  been 
produced  in  the  small  white  cone  are  trans- 
formed by  the  addition  of  more  oxygen 


WASTE  OF  OXYGEN.  53 

to  carbon  dioxide  or  carbonic  acid  gas 
(C02)  and  water  vapor  (H20).  This 
change  would  appear  to  be  two-phase  and 
may  be  better  understood  by  the  following 
equations : 

(b)  H2+0=HoO 

(c)  CO+0=C02 

The  changes  that  take  place  as  shown 
by  equations  (b)  and  (c)  do  not  and  can- 
not occur  in  the  small  white  cone  of  the 
flame,  for  the  reason  that  a  temperature 
of  6300°  F.  is  produced  at  this  point,  and 
hydrogen  and  oxygen  will  not  unite  to  form 
water  vapor  above  3600°  F.?  and  carbon 
monoxide  and  oxygen  will  not  unite  to 
form  carbon  dioxide  at  a  temperature 
higher  than  2272°  F.  In  other  words,  the 
hydrogen  and  the  carbon  monoxide  must 
get  outside  and  away  from  the  small  white 
cone  where  it  is  cooler  before  combustion 
can  take  place. 

Does  the  small  ivhite  cone  or  the  outer 
flame  or  both  take  oxygen  from  the 
tank  or  the  air? 

This  is  a  very  important  point  and  one 
which  the  conscientious  manufacturer  of 
welding  apparatus  has  seriously  studied. 
Upon  its  solution  depends  whether  the 
torch  will  be  economical  or  expensive  in 
the  consumption  of  oxygen.  Enough  oxy- 


54      OXY-ACETYLENE  WELDING  &  CUTTING. 

gen  should  be  supplied  from  the  tank  for 
the  combustion  that  takes  place  in  the 
small  white  cone  and  it  should  stop  there. 
The  outer  flame  will  take  its  oxygen  from 
the  air  if  it  is  permitted  to  do  so.  As  the 
tanked  gas  cost  money  and  the  air  is  free 
and  as  the  outer  flame  is  not  for  welding, 
economy  would  dictate  that  as  much  air  as 
possible  be  used.  It  is  a  notable  fact  that 
in  the  low  pressure  torch,  the  tendency  is 
for  the  oxygen,  by  reason  of  its  high  pres- 
sure, to  pass  through  the  small  white  cone 
and  supply  the  outer  flame  with  a  part 
of  this  element.  This  will  always  be  an 
objection  to  the  low  pressure  type  of  torch. 

What  other  objections  does  the  low  pres- 
sure torch  possess? 

In  a  series  of  experiments  carried  out 
in  France  by  the  Union  of  Autogenous 
Soldering  some  six  different  torches  using 
low  pressure  acetylene  were  tested  to  de- 
termine, first,  just  what  the  ratio  of  oxygen 
to  acetylene  was  shortly  after  ignition,  and 
second,  whether  the  ratio  was  constant 
after  the  torch  had  been  in  operation  for 
some  time  and  had  become  thoroughly 
heated.  The  results  of  these  tests  are  as 
follows : 


COMPARISON'  OF  TORCHES. 


Torch 
A 
B 
C 
D 
E 
P 

Consumption 
of  acetylene 
per  hr. 
20  Cu.  Ft. 
6  Cu.  Ft. 
12  Cu.  Ft. 
16  Cu.  Ft. 
20  Cu.  Ft. 
26  Cu.  Ft. 

Consumption 
of  oxygen 
per  hr.  shortly 
after  ignition 
28.     Cu.  Ft. 
8.1  Cu.  Ft. 
19.2  Cu.  Ft. 
26.4  Cu.  Ft. 
29.     Cu.  Ft. 
40.3  Cu.  Ft. 

Consumption 
of  oxygen 
per  hour  after 
torch  became 
hot 
36.     Cu.  Ft. 
10.     Cu.  Ft. 
22.8  Cu.  Ft. 
30.4  Cu.  Ft. 
31.     Cu.  Ft. 
45.5  Cu.  Ft. 

It  will  be  seen  from  this  table  that  there 
was  a  considerable  increase  in  the  consump- 
tion of  oxygen  upon  the  torches  becoming 
heated.  This  was  found  to  occur  only  in 
torches  using  low  pressure  acetylene.  The 
effect  of  expansion  on  the  two  gases  op- 
erating at  such  a  marked  difference  in 
pressures  is  not  the  same. 

The  clfii-itt  ltd*  been  made  here  tlt<ik  the  high 
pressure  torch  is  more  efficient  than 
the  Ion:  pressure  torch.  Will  all  high 
pressure  torches  uphold  this  conten- 
tion? 

Not  at  all.  There  are  inefficient  high 
pressure  torches  due  to  poor  design,  or 
poor  workmanship  or  both.  In  a  series 
of  tests  with  a  number  of  torches  in  which 
the  acetylene  consumption  was  fixed  at  10 
cubic  feet  per  hour  it  was  found  that  the 
best  result  showed  12%  more  oxygen  con- 
sumed than  acetylene;  the  worst  90%  more 


5()       OXY-ACETYLENE  WELDING  &  CUTTING. 

oxygen  than  acetylene,  while  the  average 
was  33%%. 

The  result  of  these  tests  should  convince 
those  who  are  using  autogenous  welding, 
or  who  are  contemplating  using  it,  that 
a  few  pieces  of  brass  do  not  constitute  an 
efficient  welding  torch. 

One  would  gather  from  the  above  that 
ivhile  the  gas  pressures  used  in  the 
various  high  pressure  torches  ivere 
practically  the  same,  the  manner  in 
which  the  gases  mix  must  be  different. 
That  is  correct.  Some  high  pressure 

torches  mix  in  the  tip,  some  in  the  head 

and  others  in  or  near  the  handle  of  the 

torch. 

Which  is  the  best  type  of  high  pressure 

torcM 

In  the  first  place,  practically  all  torches 
now  have  interchangeable  tips.  These  tips 
vary  in  size,  producing  a  small,  medium 
or  large  flame,  as  may  be  desired.  Inas- 
much as  metal  varies  in  thickness,  this  per- 
mits of  producing  a  welding  flame  of  suit- 
able size  for  the  work  at  hand.  The  writer 
is  strong  in  the  belief  that  the  torch  which 
provides  a  separate  and  distinct  mixture 
for  each  individual  tip,  will  come  the  near- 
est to  theoretical  perfection.  To  illustrate, 
Fig.  4  shows  a  cut  of  such  a  tip. 


GAS    MIXTURE    IN    TIP. 


57 


"0"  is  the  oxygen 
inlet.  "A"  "A"  is  an 
annular  chamber  in- 
which  there  are  a  num- 
ber of  holes  drilled  to 
meet  the  oxygen  inlet. 
These  openings  form 
the  acetylene  inlets  to 
a  mixing  chamber  and 
nozzle  "M. "  Between 
inlet  "0"  and  inlets 
"A"  "A"  there  is  a 
flat  seat  or  seal  which 
prevents  the  gases 
from  mixing  until  they 
reach  their  proper 
destination.  As  the 
mixing  chamber  and 
nozzle  "M"  varies  for 
each  tip,  so  the  oxygen  inlet  "0"  and  the 
acetylene  inlets  "A"  "A"  vary  accord- 
ingly, being  proportioned  to  supply  the 
correct  amount  of  acetylene  and  oxygen 
under  the  proper  pressures. 

It  must  be  clear  that  the  amount  or 
volume  of  gas  passing  through  an  opening 
depends,  upon  the  pressure  and  the  size 
of  the  opening.  Now  the  pressure  is  con- 
trolled by  the  regulators,  and  with  a  tip 
of  this  design  it  is  a  simple  matter  to  drill 


OS       OXY-ACETYLENE  WELDING  &  CUTTING. 

the  proper  openings,  once  they  have  been 
correctly  determined. 

Those  torches  which  mix  in  the  head  or 
near  the  handle  provide  no  means  of  ac- 
curately changing  the  volumes.  They 
simply  provide  for  one  mixture  and  of 
course  this  must  be  for  their  latest  tip. 
When  lighter  work  is  desired  a  smaller 
tip  which  chokes  down  the  flow  of  the  gas 
is  used.  There  can  be  no  real  accuracy 
of  mixture  with  such  a  design. 

THE   CUTTING  TORCH. 

What  metals  can  be  cut  with  the  torch? 

Wrought  iron  and  steel  are    the    only 
metals,  which  can  be  cut  with  oxygen. 
Why? 

Cutting  with  oxygen  is  simply  a  burning 
of  the  metal — a  rapid  oxidation.  The  slag 
formed  is  called  oxide  or  iron  oxide.  This 
oxide  has  a  much  lower  melting  point  than 
that  of  the  metal  and  as  the  burning  or 
cutting  progresses  the  oxide  is  detached, 
leaving  clean  iron  for  the  oxygen  to  at- 
tack. 

Copper,  brass,  aluminum  and  cast-iron 
cannot  be  cut.  These  metals  not  only  do 
not  oxidize  in  the  same  degree  as  wrought 
iron  or  steel,  but  in  addition  the  oxide 
which  does  form  has  a  melting  point  equal 
or  higher  than  that  of  the  metal  and  this 
prevents  it  from  being  detached. 


CUTTING   STEEL.  59 

Of  what  does  the  operation  of  cutting  con- 
sist? 

It  consists  first  in -heating  the  wrought 
iron  or  steel  to  redness  and  then  directing 
upon  the  heated  section  a  jet  of  oxygen 
escaping  under  a  pressure  which  varies  ac- 


An    Oxy- Acetylene    Cutting    Torch. 

cording  to  the  thickness  of  the  metal  to  be 
cut. 

In  order  to  cut  economically  and  to  secure 
a  clean,  smooth  cut,  what  is  necessary? 
That  the  torch  be  moved  at  a  regular, 
even  speed  and  that  the  speed  shall  ap- 
proach as  near  as  possible  the  maximum 
rate  at  which  the  steel  is  attacked  by  the 
oxygen;  that  pure  oxygen  shall  be  used 
and  that  the  oxygen  jet  shall  be  held  as 
close  to  the  steel  as  possible.  This  last 
is  very  important.  As  a  matter  of  fact, 
the  author,  after  considerable  experiment- 
ing, perfected  a  cutting  torch  in  which  the 
oxygen  jet  rests  directly  on  the  metal  that 
is  being  cut.  That  this  is  correct  in  prac- 
tice is  shown  by  the  cut,  which  in  the  ma- 


60       OXY-ACETYLENE  WELDING  &  CUTTING, 

jority  of  cases  is  as  smooth  as  a  shear  cut. 
We  believe  that  an  explanation  as  to 
the  theory  is  convincing  in  that  respect. 
Any  gas  when  escaping  from  an  orifice  does 
not  continue  in  a  straight  line,  but  com- 
mences to  diverge  almost  at  the  instant  it 
passes  out  of  the  opening.  This  is  illus- 
trated by  Fig.  6. 


Now  it  must  be  apparent  that  if  the  oxy- 
gen opening  is  say  %  of  an  inch  in  diameter 
that  the  diameter  of  the  oxygen  jet  must 
be  about  y2  inch  more  or  less  when  meas- 
ured a  distance  of  one  inch  from  the  noz- 
zle, and  this  diame.ter  decreases  as  we  ap- 
proach nearer  the  nozzle.  The  center  or 
core  of  this  oxygen  jet  is  probably  pure 
oxygen,  but  undoubtedly  the  outer  fringe 
is  contaminated  with  air  which  contains 
80%  nitrogen  and  it  is  this  outer  fringe 
that  is  responsible  for  the  appearance  of 
the  edge  of  the  cut — whether  clean  and 
sharp  or  rough  and  cindery.  Elsewhere 
we  have  shown  the  effect  of  impure  oxygen 
in  cutting  and  if  the  results  of  these  tests 


COST   OF    CUTTING.  61 

can  be  relied  upon  it  bears  out  the  above 
claims. 

Another  advantage  in  resting  the  oxy- 
gen jet  directly  on  the  metal  is  that  the 
cut  is  narrower,  therefore  less  metal  has 
been  burned  and  the  operation  is  more 
economical. 

Who  tvere  probably  the  first  to  use  oxygen 
for  cutting? 

Dr.  Menne,  a  German,  and  Jbttrand,  a 
Belgian. 

Theoretically,  hoiv  much  oxygen  is  required 
to  cut  a  given  amount  of  steel? 

As  previously  stated,  the  steel  when  cut 
is  transformed  into  iron  oxide  or  more 
properly  magnetic  oxide  of  iron,  the  chem- 
ical symbol  of  which  is  Fe:,  04.  The  atomic 
weight  of  iron  is  55.9  and  that  of  oxygen 
16,  so  that  the  weights  of  the  iron  (Fe) 
and  the  oxygen  (0)  in  the  iron  oxide  are 
in  the  proportion  of  168  to  64  or  21  to  8. 
The  oxygen  needed  will  then  be  8/21  times 
the  weight  of  the  steel  involved,  or  38% 
of  the  weight  of  the  steel  removed.  As- 
suming that  the  kerf  or  cut  has  a  thickness 
or  width  of  Vs-inch,  the  weight  of  steel 
corresponding  to  each  square  inch  of  the 
face  of  the  cut  is  .0352  pound,  and  38% 
of  this  is  .01338  pound,  the  weight  of  oxy- 
gen necessary  to  make  the  cut.  A  pound 
of  oxygen  at  32°  F.  occupies  11.2  cubic  feet 


62       OXY-ACETYLENE  WELDING  &  CUTTING. 

of  space,  and  .01338  pound  is  found  to  be 
.15  cubic  foot.  Therefore,  theoretically  it 
requires  .15  cubic  foot  of  oxygen  to  cut  a 
square  inch  of  steel  if  the  kerf  is  Vs-inch 
wide. 

In  practice  wliat  amount  of  oxygen  lias 

been  found  necessary? 
Just  about  double  the  theoretical  amount. 
It  must  b6  remembered  that  the  above  has 
considered  only  the  amount  of  oxygen  re- 
quired in  the  oxygen  jet.  To  this  must  be 
added  the  oxygen  and  the  acetylene  con- 
sumed in  the  heating  jets. 


L^  the  rt^ajiy  detrimental  cltanye  in  material 

*wrien  cut  with  oxugenf^ 

Xo.  On  high  carbon  steels  there  is  a 
slight  softening  of  the  metal  for  a  distance 
of  about  %-inch  from  the  cut,  due  to  the 
annealing  effect  of  the  heat.  Numerous 
tests  have  been  made  and  all  bear  out  the 
above  assertion.  The  results  of  one  such 
test  may  prove  interesting.  A  steel  plate 
%-inch  thick  and  14%-inch  long  was  used. 

TEST    NO.    1.  TEST    NO.    2. 

ORIGINAL  STOCK  BEFORE 


CUT. 

Tensile 47,620  Ibs. 

Elastic  Limit.  .31,640  Ibs. 

Elongation 33% 

Reduction  of  area. .  .35% 


AFTEK  CUT. 

50,110  Ibs. 

29,930  Ibs. 

33% 

42% 


OTHER  HEATING  AGENCIES.  DO 

Can  a  fuel  gas  other  than  acetylene  be  used 
in  the  pre-heating  jet? 

Yes.  Ordinary  coal  gas,  Pintsch  gas, 
hydrogen  or  any  good  hydro-carbon  gas 
can  be  used. 

Hydrogen  has  been  used  quite  extensive- 
ly for  cutting,  and  for  extremely  heavy 
work  would  seem  to  be  better  adapted  than 
acetylene.  The  hydrogen  flame  is  a  long 
one,  whereas  the  acetylene  flame  is  short, 
and  this  is  probably  the  reason  why  on 
very  thick  metal  hydrogen  would  seem  to 
be  better  adapted. 

The  cost  depends  largely  upon  the  price 
at  which  the  two  gases  can  be  purchased, 
and   when  any  comparison  is    made    the    % 
market  price  of  each,  together  with  the  con- 
sumption, should  be  stated. 


CHAPTER  IV. 

APPARATUS  AND  INSTALLATION. 
REGULATORS  AND  REDUCERS. 

The  above  names  used  to  designate  a 
part  of  the  welding  and  cutting  apparatus 
would  appear  to  be  used  synonymously  in 
this  country.  However,  the  function  of  a 
regulator  would  seem  to  be  wider  in  its 
scope  than  that  of  a  reducer.  A  good  regu- 
lator is  a  very  essential  part  of  any  welding 
or  cutting  equipment. 
What  is  the  duty  or  function  of  a  regulator? 

Primarily  to  reduce  the  pressure  of  the 
oxygen  as  it  flows  from  the  cylinder,  and 
the  pressure  of  the  acetylene  from  its  tank, 
or  the  generator  as  the  case  may  be.  Its 
secondary  duty  is  to  maintain  the  desired 
reduced  pressure  without  fluctuating.  Al- 
most any  type  of  regulator  will  fulfill  the 
first  requirement,  but  only  a  high  grade 
one  combines  both  features. 
How  are  regulators  constructed® 

They  all  utilize  the  diaphragm  principle. 
The  diaphragm  is  either  of  metal  or  rub- 
ber composition  and  attached  to  one  side 
of  the  diaphragm  is  a  seat  which  covers 
and  closes  the  opening  in  a  nipple  com- 
municating with  the  gas  cylinder.  There 
is  a  spring  which  rests  against  the  other 

64 


CONSTRUCTION   OF  REGULATOR. 


65 


G/7S   OVTl-ET 


Fig:.  7. 
An  Oxygen  Regulator. 


side  of  the  diaphragm.    When  there  is  no 
tension  on  this   spring,  the  parts   are   so 


66       OXY-ACETYLENE  WELDING  &  CUTTING. 

adjusted  that  the  diaphragm  holds  the  seat 
over  the  nipple,  closing  the  gas  inlet  tight, 
so  that  no  gas  can  escape  from  the  con- 
tainer. When  some  tension  is  put  on  the 
spring,  the  diaphragm  is  pushed  inward, 
releasing  the  pressure  of  the  seat  on  the 
nipple  and  allowing  the  gas  to  flow  into 
the  body  of  the  regulator.  The  pressure 
of  the  gas  climbs  until  it  exceeds  the  ten- 
sion of  the  spring  when  the  diaphragm  is 
pushed  outward,  again  closing  the  gas  in- 
let. The  gas  that  is  in  the  body  of  the 
regulator  is  used  up  by  the  torch  until  the 
pressure  drops  to  a  point  where  the  spring- 
tension  is  the  stronger,  and  the  seat  opens, 
allowing  gas  to  again  enter  the  regulator. 
This  continues  regularly  and  might  very 
aptly  be  compared  to  breathing.  If  the 
seat  is  perfect,  and  the  flexibility  of  the 
diaphragm  correctly  proportioned  to  the 
stiffness  of  the  spring,  a  very  sensitive  reg- 
ulation can  be  obtained. 

Should  an  oxygen  regulator   be   provided 

with  a  cock  or  valve  at  its  outlet? 
No,  for  the  reason  that  if  a  cock  is 
furnished  at  the  outlet,  there  is  always  the 
temptation  for  the  operator,  when  the  torch 
is  not  in  use,  to  shut  off  the  gas  at  this 
point  rather  than  at  the  tank  valve.  If  the 
regulator  seat  should  leak,  trouble  might 
result,  whereas  if  there  was  no  cock  a 


CARE  OF  REGULATOR.  67 

burst  hose  would  be  the  only  bad  result. 

What  are  some  of  the  points  to  be  observed 
in  order  to  keep  a  regulator  in  good 
condition? 

As  stated  above,  the  diaphragm  is  con- 
tinually breathing  or  moving  and  of  course 
the  seat  is  subjected  to  considerable  wear 
by  the  reason  of  its  frequent  closing  and 
opening  of  the  inlet  nipple.  If  the  seat 
is  not  perfect,  it  is  of  no  value  and  so  care 
must  be  taken  that  the  movement  of  the 
diaphragm  closing  the  seat  is  not  sudden, 
as  the  seat  will  pound  on  the  nipple  and 
quite  likely  be  destroyed.  This  is  caused 
by  the  operator  opening  the  tank  valve 
while  there  is  tension  on  the  regulator 
spring,  so  if  you  expect  your  regulator  to 
give  good  service,  see  that  the  spring  ten- 
sion  is  released  before  turning  on  the  gas. 

We  have  just  seen  how  the  regulator  seatf 
could  be  injured  by  the  diaphragm  being 
suddenly  forced  outward  by  the  incoming 
gas.  The  diaphragm  itself  may  be  put 
out  of  commission  and  possibly  injury  done 
the  seat  by  reducing  from  a  higher  to  a 
lower  pressure  with  the  outlet  closed. 

To  illustrate,  suppose  that  the  torch  is 
welding  on  heavy  work  which  requires  an 
oxygen  pressure  of  18  or  20  pounds  and 
it  is  necessary  to  do  some  light  welding. 
This  requires  a  small  tip  with  an  oxygen 


68       OXY-ACETYLENE  WELDING  &  CUTTING. 

pressure  of  2  or  3  pounds.  If  the  thumb 
screw  is  backed  out,  releasing  the  tension 
on  the  spring  there  will  be  little  or  no  ten- 
sion against  the  diaphragm  on  the  spring 
side  and  it  will  be  forced  outward,  and  in 
time  so  buckle  the  diaphragm  that  it  will 
be  useless.  Th^refore 
the  higher  to  a  ^ 


regulator? 
A  regulator  leaks  when  the  seat  does  not 
completely  seal  the  opening  in  the  inlet 
nipple  and  allows  the  gas  from  the  tank 
to  enter  the  body  of  the  regulator.  A  leak- 
ing regulator  is  detected  by  the  hand  on 
the  low  pressure  gauge,  which  is  usually 
the  small  gauge,  creeping  up.  When  the 
hand  indicator  on  this  gauge  shows  the 
pressure  creeping  15  or  20  pounds  more 
than  the  pressure  shown  when  the  torch 
is  operating,  then  there  is  a  serious  leak 
and  it  is  dangerous  to  continue  using  a 
regulator  under  this  condition.  When  this 
occurs  the  regulator  should  be  returned  to 
the  manufacturer  for  repairs.  While  some 
undoubtedly  wrould  be  able  to  repair  their 
own  regulators,  in.  the  vast  majority  of 
cases  it  would  be  much  more  satisfactory 
to  return  them  to  the  manufacturer  who 
would  be  in  a  position  to  put  them  in  first- 
class  shape. 


GAUGES.  69 

It  is  important  that  no  grease  or  oil 
be  allowed  in  the  interior  of  the  regulator. 
If  this  should  be  done  it  might  cause  an 
explosion. 

GAUGES. 

The  better  class  of  apparatus  manufac- 
turers equip  oxygen  regulators  with  two 
gauges,  one  of  which  is  a  3000-lb.  gauge 
and  the  other  ranging  from  50  pounds  to 
150  pounds.  The  3000-lb.  gauge  usually 
reads  not  only  in  pounds  pressure,  but  also 
in  cubic  feet,  so  that  by  glancing  at  this 
gauge  the  operator  can  instantly  note  both 
the  pressure  in  the  tank  and  the  cubic  con- 
tents. The  other  gauge,  which  is  usually 
of  smaller  diameter,  indicates  the  pressure 
under  which  the  torch 'is  operating.  The 
3000-lb.  gauge  *should  be  provided  with 
what  is  known  as  a  safety  back  so  that  in 
the  event  that  the  spring  should  prove  de- 
fective and  burst,  injury  to  the  operator 
will  be  avoided. 

GOGGLES. 

Tinted  or  smoked  goggles  should  always 
be  worn  by  those  welding.  The  tint  or  de- 
gree of  color  depends  entirely  upon  in- 
dividual taste.  For  welders  doing  general 
repair  work  a  light-smoked  and  also  a  dark- 
smoked  goggle  should  be  provided,  the 
lighter  colored  goggle  being  used  on  alum- 


70      OXY-ACETYLENE  WELDING  &  CUTTING. 

inum,  brass  or  small  castings,  while  the 
darker  goggles  should  be  worn  on  heavy 
cast-iron  and  steel  work. 

Some  welders  unquestionably  wear 
glasses  of  too  dark  a  color,  the  strain  on 
the  eye  trying  to  see  the  work  being  as 
injurious  as  if  they  wore  none  at  all.  The 
best  color  is  the  one  which  does  not  tire 
or  strain  the  eye. 

ACETYLENE  GENERATOR. 

One  of  the  most  important  units  that 
comprise  an  oxy-acetylene  welding  plant  is 
the  acetylene  generator.  As  previously 
stated,  these  are  of  two  types,  namely  low 
pressure  and  high  pressure.  Nearly  every- 
one is  familiar  with  the  low  pressure  gen- 
erator by  reason  of  the  fact  that  it  is  simply 
a  lighting  generator.  The  high  pressure 
generator  produces  the  acetylene  under  a 
few  pounds  pressure. 
What  are  the  important  considerations  in 

an  acetylene  generator? 
They  are: 

1st  —Safety. 

2nd — Cool  generation. 

3rd — Automatic  feed. 

4th — Minimum  variance  in  pressure. 

5th — Good  mechanical  construction. 
What  devices  should  be  placed  on  a  gen- 
erator to  insure  safety? 
The  most  important  consideration  from 


ACETYLENE    GENERATOR.  71 

a  standpoint  of  safety  is  that  the  feeding 
mechanism  on  the  generator  should  be  ar- 
ranged so  that  it  will  lock  when  a  given 
amount  of  gas  has  been  generated  and  this 
means  when  a  given  amount  of  carbide  has 
been  fed  into  the  water.  If  the  locking  de- 
vice did  not  operate,  it  must  be  apparent 
that  an  excess  amount  of  gas  would  be 
generated. 

In  the  low  pressure  generator  the  gas 
might  break  the  water  seal  and  so  escape 
into  the  room. 

In  the  high  pressure  generator  an  ex- 
cessive pressure  might  occur. 

Safety  blow-offs  are  provided  on  all  first- 
class  generators  and  these,  if  operating, 
would  prevent  the  gas  from  escaping  into 
the  room,  but  in  any  event  there  would  be 
a  loss  of  gas  which  would  be  pure  waste. 

A  flash-back  cylinder  is  necessary  on 
either  type  of  machine.  While  the  chance 
of  the  flame  flashing  back  in  the  generator 
is  rather  remote,  yet  there  is  the  possibility 
of  such  a  thing  happening  and  safety  de- 
vices of  this  kind  should  be  attached  to  all 
generators. 

COOL-GENERATION. 

Under  the  head  of  Acetylene  cool-gen- 
eration was  briefly  described.  By  this  is 


72       OXY-ACETYLENE  WELDING  &  CUTTING. 

meant :  supplying  a  sufficient  amount  of 
water  to  dissipate  or  keep  down  the  heat 
of  generation.  It  is  imperative  that  one 
gallon  of  water  should  be  supplied  for  each 
one  pound  of  carbide  in  the  generator. 

AUTOMATIC  FEED. 

What  is  meant  by  Automatic  Feed? 

By  this  is  meant  that  the  generator  will 
automatically  without  attention  feed  car- 
bide and  thereby  generate  gas  for  the  torch 
as  it  is  being  used,  and  will  cease  generat- 
ing when  the  torch  is  not  in  use.  Some 
machines  do  not  do  this  and  it  seriously  in- 
terferes with  the  welder,  as  it  is  necessary 
for  him  every  few  minutes  to  leave  his 
work  and  feed  by  hand  some  carbide. 

MINIMUM  VARIANCE  IN  PRESSURE. 

In  the  low  pressure  generator  there  is 
practically  no  yariance  in  pressure.  With 
the  high  pressure  generator  there  is  and 
must  be  a  slight  variance  in  pressure.  It 
is  this  slight  difference  in  pressure  which 
is  taken  advantage  of  to  start  and  stop 
the  "feeding  mechanism.  This  variance  in 
pressure  should  not  exceed  a  pound  or 
two  and  this  is  taken  care  of  by  means 
of  a  special  regulator  for  high  pressure 
generators. 


CONSTRUCTION.  73 

GOOD  MECHANICAL  CONSTRUCTION. 

It  is  admitted  by  all  that  any  machine 
should  have  good  mechanical  construction 
and  the  only  difference  arising  is  as  to 
what  constitutes  good  mechanical  construc- 
tion. It  is  the  opinion  of  the  writer  that 
welding  generators  should  be  built  very 
much  more  substantial  than  the  ordinary 
acetylene  lighting  generator,  for  the  rea- 
son that  very  much  more  work  is  demanded 
of  the  welding  generator  than  is  of  the 
lighting  machine. 

Some  machines  have  the  body  of  gen- 
erator riveted  and  soldered.  We  are 
strongly  of  the  belief  that  this  is  a  mistake. 
The  generator,  of  course,  must  be  gas-tight 
and  as  the  rivets  do  not  produce  a  gas- 
tight  joint,  soldering  is  resorted  to.  The 
sheets  are  usually  galvanized  iron.  Sheet 
metal  workers  have  long  since  learned  that 
where  solder  is  applied  to  galvanized  stock 
if  the  parts  are  subject  to  any  movement 
or  strain  the  galvanizing  will  peel  and,  of 
course,  as  the  solder  is  attached  to  the  gal- 
vanizing it  means  a  loose  and  leaky  joint. 
The  pressure  in  the  acetylene  generator 
varies  and  this  causes  a  breathing  of  the 
body  or  tank  portion  and  in  time  the  solder 
breaks  loose  and  the  gas  leaks  into  the 
room.  Too  often  in  attempting  to  solder 
up  these  loose  joints  an  open  light  has 


74      OXY-ACETYLENE  WELDING  &  CUTTING. 

been  used  with  fatal  results.  The  best 
generators  have  all  of  the  seams  and  con- 
nections welded.  It  would  seem  to  reflect 
upon  the  oxy-acetylene  process  to  do  other- 
wise. 

The  motor  which  operates  the  feeding 
machine  should  be  strong  and  substantial. 
If  there  is  any  possible  chance  of  gears 
in  time  stripping  or  breaking,  devices 
should  be  arranged  to  automatically  lock 
the  motor. 

PORTABLE  GENERATORS. 

There  are  some  firms  who  advocate  the 
placing  of  an  acetylene  generator  upon  a 
truck  and  using  it  for  portable  work.  The 
writer  cannot  condemn  in  too  strong  terms 
such  practice.  There  is  no  objection  in 
moving  the  generator  when  there  is  no  car- 
bide in  it  to  where  the  work  is  to  be  done 
and  then  charging  the  generator,  but  to 
move  a  generator  containing  carbide  and 
water  through  buildings  where  there  are 
large  insurable  values  is  a  great  mistake 
and  is  apt  to  result  in  loss  of  property  and 
possibly  life. 

DIRECTIONS    FOR    CONNECTING    UP    TANK    OR 
PORTABLE  WELDING  OUTFIT. 

We  shall  take  up  first  the  installation 
of  a  welding  unit  in  which  both  the  acety- 
lene and  the  oxygen  are  used  from  tanks 


INSTALLING  TANK  OUTFIT.  /5 

or  cylinders.  These  are  known  by  the 
trade  as  "tank"  outfits.  Before  attempt- 
ing* to  light  the  torch,  the  novice  should 
thoroughly  learn  how  the  different  parts 
should  be  assembled,  and  he  should  know 
the  function  of  each  separate  part  of  the 
equipment. 

(1)  With  the  portable  or  tank  outfit  it 
is  necessary  to  have  two  tanks.     One  of 
these  contains  oxygen,  and  it  is  so  stamped 
or  labeled.     The  other  contains  acetylene, 
and  this  tank  is  plainly  marked  acetylene. 
They  are  both  gases,  but  have  entirely  dif- 
ferent properties.    Learn  to  call  them  by 
their  correct  names  of  oxygen  and  acety- 
lene. 

(2)  All  oxygen  tanks  have   a  cap   for 
protecting   the   tank    valve   in    shipment. 
Eemove  this  cap  by  unscrewing  and  at- 
tach the  oxygen  regulator,  being  sure  that 
the  coupling  nut  is  drawn  up  tight  to  pre- 
vent leakage.     It  is  impossible  to  attach 
the  wrong  regulator  as   only  the  oxygen 
regulator   connection  will  fit   the   oxygen 
tank  valve.     Then  attach  the  oxygen  hose 
to  the  regulator  outlet. 

(3)  If  a  Prest-0-Lite  Acetylene  tank  is 
used,  an  adapter  must  first  be  screwed  in- 
to the  tank  valve.    This  adapter  has  a  left- 
hand  screw  connecting  to  the  tank.       If 
Commercial  Acetylene  or  Searchlight  tanks 


76      OXY-ACETYLENE  WELDING  &  CUTTING. 

are  used  the  adapter  is  not  necessary. 
When  outfit  is  ordered,  you  should  specify 
which  make  of  acetylene  tank  you  con- 
template using  so  that  the  manufacturer 
may  furnish  the  right  connection.  If  a 
Prest-0-Lite  tank  is  used,  when  the  regu- 
lator is  connected  it  will  be  upright.  If 
Commercial  or  Searchlight  tank  is  used 
the  regulator  will  form  a  right  angle  with 
the  tank.  Be  sure  that  the  connection  is 
tight  and  well  made  so  that  there  will  be 
no  leaks.  Then  attach  the  acetylene  hose 
to  the  regulator  outlet. 

(4)  Attach  the  oxygen  hose  to  the  cock 
at  the  torch  handle  which  is  stamped  with 
the  letter  "0"  or  with  the  word  oxygen. 
With  most  torches  this  is  the  upper  cock. 
Then  attach  the  acetylene  hose  to  the  cock 
at  the  torch  handle  which  is  stamped  with 
the  letter  "A"  or  with  the  word  acety- 
lene.   With  most  torches  this  is  the  lower 
cock. 

(5)  The  correct  welding  tip  should  be 
selected  and  screwed  tightly  into  the  torch 
head.     Practically  all  manufacturers  fur- 
nish a  table  showing  the  size  of  tip  that 
should  be  used  for  different  thicknesses  of 
metal.     These  tables  are  practically  cor- 
rect, but  some  latitude   must   be    allowed, 
as  the  mass  of  metal  and  the  kind  of  metal 
will  necessitate  some  variation. 


INSTALLING.  TANK    OUTFIT.  (  t 

(6)  Now  see  that  the  regulator  screws 
on  both  the   acetylene  and  oxygen   regu- 
lators are  entirely  released — that  is,  backed 
out  or  turned  to  the  left  until  they  are  free 
of  tension. 

(7)  SLOWLY  open    the    oxygen    tank 
valve  when  the  pressure  and  contents  will 
register  on  the  dial  of  the  3000-lb.  gauge. 

(8)  Open  the  acetylene  tank  valve  and 
the  pressure  of  the  gas  in  this  tank  will 
register  on  the  dial  of  the  500-pound  gauge. 

(9)  Turn  the  acetylene  regulator  screw 
to  the  right   slowly  until  the  number  of 
pounds  pressure  registered  on  the  small 
gauge  is  the  same  as  shown  in  the  manu- 
facturer's table  under  the  head  of  acety- 
lene for  that  size  of  tip.    This  small  gauge 
indicates  the  acetylene  pressure  being  de- 
livered through  the  hose  to  the  torch. 

(10)  Turn  the  oxygen  regulator  screw 
to  the  right   slowly  until  the  number   of 
pounds  pressure  registered  on  the  small 
gauge  is  the  same  as  shown  in  the  manu- 
facturer's table  under  the  head  of  oxygen 
for  that  size  of  tip.     This  small  gauge  in- 
dicates the  oxygen  pressure  being  delivered 
through  the  hose  to  the  torch. 

(11)  Open  the  acetylene  torch  cock  and 
light  the  acetylene  and  then  slowly  open 
the  oxygen  cock  and  continue  to  open  until 
the  neutral  flame  is  obtained.    Occasionally7 


78       OXY-ACETYLENE  WELDING  &  CUTTING. 

open  or  close  one  of  the  torch  cocks  to  see 
that  proper  flame  regulation  is  being  main- 
tained. 

(12)  While  operating  should  the  flame 
pop  out,  what  is  commonly  called  a  "back- 
flash"  has  occurred.  This  is  caused  by 
one  of  three  things: 

First     —The  tip  becoming  overheated. 

Second — A  piece  of  molten  metal  flying 
up  and  momentarily  closing  the 
orifice  of  the  tip. 

Third  — By  an  insufficient  amount  of 
pressure  of  either  acetylene  or 
oxygen. 

Should  this  occur,  you  should  quickly 
close  first  the  oxygen  torch  valve  and  then 
the  acetylene  torch  valve.  Then  relight  the 
torch. 

Sometimes  in  operating  a  welding  torch 
the  smaller  tips  work  correctly,  but  trouble 
is  experienced  in  getting  the  larger  tips 
to  stay  lighted.  If  upon  investigation  none 
of  the  three  troubles  mentioned  above  are 
responsible,  then  it  is  quite  likely  that  dirt 
has  gotten  in  the  torch  tubes  and  partly 
closed  some  of  the  openings.  This  dirt 
can  come  from  the  hose  or  other  causes. 
By  partly  closing  the  openings  they  will 
still  be  large  enough  to  supply  enough  gas 
for  the  smaller  tips,  but  will  not  be  large 
enough  for  the  larger  tips. 


INSTALLING  GENERATOR   OUTFIT.  79 

It  will  therefore,  be  necessary  to  attach 
a  hose  to  the  tip  end  of  the  torch  and  by 
using  either  compressed  air  or  oxygen 
from  the  tank  blow  the  dirt  out  through 
the  handle. 

DIRECTIONS  FOR  INSTALLING  GENERATOR 
WELDING  OUTFIT. 

GENERATOR  INSTALLATION. 

We  now  come  to  installation  of  a  weld- 
ing plant  which  uses  acetylene  from  a  gen- 
erator instead  of  from  a  compressed  tank. 
The  first  question  that  suggests  itself  is 
regarding  the  foundation. 

GENERATOR  FOUNDATION. 

This  may  be  of  brick,  stone,  concrete, 
iron  or  of  wood.  If  of  wood  then  it  should 
he  of  extra  heavy  timbers  arranged  so  that 
the  air  can  circulate  around  them  and  ar- 
ranged so  as  to  form  a  substantial  and  firm 
base.  It  should  be  seen  that  the  generator 
is  level  and  that  no  unequal  strain  is  placed 
on  it  or  any  of  the  connections. 

We  would  strongly  recommend  that 
where  possible  the  generator  be  placed 
outside  of  insured  buildings  in  properly 
constructed  generator  houses.  This  is 
greatly  to  be  desired,  particularly  if  the 
insurable  values  are  high,  for  the  reason 
that  if  the  generator  is  located  outside  in  a 
separate  detached  building  most,  if  not  all, 


80       OXY-ACETYLENE  WELDING  &  CUTTING. 

of  the  states  make  no  charge  to  the  insur- 
ance rates,  whereas  if  the  generator  is  lo- 
cated inside  of  any  of  the  main  buildings 
there  is  an  increased  premium  rate.  The 
generator  should  be  placed  so  that  there 
will  be  ample  room  both  for  the  machine 
and  the  attendant  to  perform  his  required 
duties.  Windows  or  skylights  should  be 
provided  so  there  will  be  no  need  for  arti- 
ficial light.  In  climates  where  there  is 
danger  from  freezing,  proper  protection 
should  be  provided  to  guard  against  it. 
Steam  or  hot  water  heat  only  should  be 
used. 

ESCAPE  OR  VENT  PIPES. 

All  generators  of  standard  make  are  pro- 
vided with  an  escape  or  vent  pipe.  This 
should  be  of  ample  size,  in  no  case  to  be 
less  than  %-inch  internal  diameter.  This 
pipe  should  be  installed  without  traps  and 
so  that  any  condensation  will  drain  back 
to  the  generator.  It  must  be  carried  to 
a  suitable  point  outside  the  building  and 
terminate  in  a  hood  located  at  least  12 
feet  from  the  ground.  The  hood  must  be 
constructed  in  such  a  manner  that  it  can- 
not be  obstructed  by  rain,  snow,  ice,  insects 
or  birds. 

CAPACITY. 

Generators  should  be  of  sufficient  ca- 
pacity to  furnish  gas  under  working  con- 


PIPING.  81 

ditions  from  one  charge  of  carbide  to  all 
torches  installed,  for  at  least  one  working 
period  of  one-half  day  or  4y2  hours.  For 
the  better  class  of  machines — carbide  feed 
— the  rating  has  been  fixed  at  one  cubic 
foot  of  gas  per  hour,  per  pound  of  carbide. 
As  an  example  a  50-pound  machine,  that 
is;  one  having  a  capacity  of  50  pounds  of 
carbide  per  charge,  would  have  a  rated 
capacity  of  50  cubic  feet  of  acetylene  per 
hour. 

PIPING. 

Connections  from  the  generator  to  serv- 
ice pipes  should  preferably  be  made  with 
right  and  left  couplings  or  long  thread 
nipples  with  lock  nuts,  Where  unions  are 
used  these  should  be  of  a  type  which  obvi- 
ates the  necessity  for  using  gaskets.  Where 
possible,  the  piping  should  be  arranged  so 
that  any  moisture  will  drain  back  to  the 
generator.  If  low  points  necessarily  oc- 
cur in  any  piping,  it  should  be  drained 
through  tees  into  drip  cups  permanently 
closed  with  screw  caps  or  plugs.  In  no 
event  use  pet-cocks. 

In  large  installations  where  the  service 
pipe  extends  a  considerable  distance,  thej 
main  service  pipe  should  be  broken  at  a  ( 
point  as  close  to  the  generator  as  possible.  ] 
The  connection  here  should  be  made  out 
of  strong  and  substantial  rubber  hose.   Thej 


82       OXY-ACETYLENE  WELDING  &  CUTTING. 

object  of  this  rubber  hose  is  to  secure 
electrical  insulation]  Some  accidents  have 
occurred  by  reason  of  electricity  used  in 
the  plants  grounding  on  the  acetylene  serv- 
ice pipe  and  causing  a  spark  while  the 
generator  was  being  charged.  Insulation 
as  recommended  above  will  prevent  this. 

The  schedule  of  pipe  sizes  for  piping 
from  the  generator  to  torches  should  con- 
form to  that  commonly  used  for  ordinary 
gas,  but  in  no  case  must  feeders  be  smaller 
than  %-inch. 

Generators  should  not  be  directly  con- 
nected to  sewers,  but  should  discharge  into 
suitable  open  receptacles  which  may  be 
provided  with  an  overflow  pipe  connected 
to  the  sewer.  Piping  should  be  carefully 
tested  when  system  is  completed.  It  must 
not  show  a  loss  in  excess  of  1  pound  with- 
in 12  hours  when  subjected  to  a  pressure 
of  8  pounds. 

CARE  AND  MAINTENANCE. 

Generators  should  be  cleaned  and  re- 
charged as  nearly  as  possible  at  regular 
stated  intervals.  This  work,  as  well  as 
any  repairs,  should  be  done  during  daylight 
hours  only  when  artificial  light  is  not 
needed.  When  artificial  light  is  absolute- 
ly necessary,  this  must  be  provided  by  in- 
candescent electric  lights  enclosed  in  gas 
tight  globes.  In  charging  generator  clean 


MAINTENANCE.  80 

all  of  the  residue  out  thoroughly,  and  then 
fill  with  the  required  amount  of  water. 
Never  charge  with  carbide  unless  generator 
is  filled  with  water.  Always  keep  flash- 
back chamber  filled  with  watef. 

CONNECTING   REGULATORS. 

When  the  generator  and  the  service  pip- 
ing leading  therefrom  has  been  installed, 
attach  the  acetylene  generator  regulators 
to  the  piping  at  the  various  locations  pre- 
viously determined  as  welding  stations. 
Connect  the  acetylene  hose  to  the  regulator 
Individual  oxygen  tanks  can  be  used  at 
the  various  welding  stations  or  a  number 
of  oxygen  tanks  can  be  connected  to  a 
manifold  provided  with  a  regulator  -and 
the  gas  piped  at  a  reduced  pressure  wher- 
ever required.  Connecting  the  torch  is 
the  same  as  for  the  tank  plant. 

A  FEW  DON'TS. 

Never  recharge  generator  without  first 
cleaning  out  the  generating  chamber  and 
completely  refilling  with  water. 

Never  test  the  generator  or  piping  for 
leaks  with  a  flame,  and  never  apply  flame  to 
any  open  pipe  or  at  any  point  other  than 
the  torch.  In  testing  for  leaks  use  soap 
and  water. 

Never  use  a  lighted  match,  lamp,  candle, 
lantern  or  any  open  light  near  the  gen- 
erator. 


CHAPTER  V. 

PREPARING  FOR  WELDING. 
TOOLS  NECESSARY  FOR  REPAIR 

WELDING. 

Probably  90%  of  those  who  purchase 
welding  apparatus  already  have  all  neces- 
sary tools  for  the  welding  shop,  but  for 
the  benefit  of  the  remaining  10%  we  would 
say  that  one  should  have  a  vise,  clamps, 
files,  stillson  and  monkey  wrenches,  tongs, 
chisels,  hammer,  forge,  stationary  emery 
and  if  possible  a  portable  one  also,  chain- 
block,  V-blocks,  square  and  stiaight  edge, 
portable  kerosene  torch,  a  number  of 
small  pieces  of  iron  or  steel  ranging  in 
thickness  from  that  of  a  saw-blade  on  up, 
to  be  used  as  shims,  hack-saw,  about  200 
fire  brick,  roll  of  asbestos  paper,  and  a 
welding  table. 

The  welding  table  is  the  only  accessory 
that  requires  a  description.  If  one  is  in 
a  town  where  there  is  a  scrap-iron  dealer,  a 
cheap  and  serviceable  table  can  usually  be 
found  in  his  scrap  pile  and  obtained  for 
the  price  of  ordinary  junk.  If  possible, 
secure  an  old  casting  that  has  been  ma- 
chined on  one  side  and  is  at  least  two  or 
three  inches  thick  so  that  it  will  not  be 
easily  warped  by  the  heat.  An  old  planer 

84 


CLEANING  AND  BEVELING.  85 

bed  makes  an  excellent  table  if  you  should 
be  fortunate  enough  to  find  one.  If  it  is 
impossible  to  procure  such  a  casting,  then 
it  will  be  necessary  to  make  a  table  about 
30  inches  high  of  either  angle  iron  or  bar 
stock  and  cover  it  with  brick. 

CLEANING  THE  METAL. 

The  edges  to  be  welded  and  the  immedi- 
ate vicinity  of  the  weld  should  be  thorough- 
ly cleaned.  Not  only  will  the  welding  be 
facilitated  by  doing  so,  but  it  also  prevents 
the  dirt,  oxide,  etc.,  from  being  incorpo- 
rated in  the  molten  metal  and  assisting  if 
not  actually  forming  blow-holes. 

If  the  work  is  well  cleaned,  less  flux  will 
be  required  and  that  which  is  used  will  do 
its  work  better. 

BEVELING. 

Where  the  metal  to  be  welded  is  of  a 
thickness  of  3/16  of  an  inch  or  more,  the 
edges  should  be  beveled  so  that  when  the 
two  pieces  are  placed  together  they  form 
an  angle  of  at  least  90  degrees. 

In  steel  of  %  of  an  inch  in  thickness  or 
more  this  bevel  should  be  of  an  even  great- 
er angle. 

Beveling  can  be  accomplished  by  either 
grinding,  chipping  or  sawing  and  it  is 
necessary  for  several  reasons.  By  remov- 
ing the  metal,  this  allows  the  flame  to  get 


86      OXY-ACETYLENE  WELDING  &  CUTTING. 

down  to  the  bottom  and  work  its  way  up 
and  it  permits  of  adding  a  greater  quanti- 
ty of  metal  of  better  quality.  Some  weld- 
ers do  not  bevel,  but  depend  upon  the  torch 
to  flow  the  metal  out  or  they  dislodge  it 
when  molten  by  means  of  a  rod. 

In  the  great  majority  of  cases  this  is 
bad  practice.  Occasionally  where  it  would 
be  difficult  to  "line  up"  the  casting  after 
it  was  ground,  beveling  may  be  dispensed 
with.  Those  welders  who  make  a  practice 
of  welding  without  beveling  will  be  very 
apt  to  be  troubled  with  "come-backs"  and 
an  examination  of  their  work  will  deter- 
mine that  they  have  not  welded  all  the  way 
through,  or  that  they  have  burned  the 
metal. 

When  the  part  to  be  welded  is  %  of  an 
inch  thick  or  more,  it  is  best  to  bevel  and 
weld  on  both  sides  if  it  is  possible  to  do  so. 

PRE-HEATING    METHODS    AND    DEVICES. 
CHARCOAL. 

Probably  the  first  method  of  pre-heating 
was  the  use  of  charcoal.  This  fuel  is  still 
used  to  a  considerable  extent.  It  has  the 
advantages  of  a  slow  heat,  an  even  one 
and  a  fairly  high  temperature.  The  slow 
heat,  while  an  advantage  on  some  castings 
is  a  disadvantage  on  others.  There  is  one 
serious  objection  and  that  is  the  disagree- 


PRE-HEATING   FUELS.  87 

able  fumes  which  accompany  its  combus- 
tion. 

ARTIFICIAL  OR  NATURAL  GAS. 

In  the  cities  and  in  certain  sections  of 
the  country,  it  is  possible  to  procure  one 
of  the  above  gases.  Where  gas  can  be  ob- 
tained, this  makes  an  ideal  fuel  for  pre- 
heating when  used  in  connection  with  prop- 
erly designed  torches.  The  inlet  service 
main  into  the  building  should  be  sufficiently 
large  to  furnish  an  adequate  flow  of  gas. 
This  pipe  should  not  be  less  than  2  inches 
in  diameter.  For  cylinder  work,  or  where 
the  pre-heating  is  primarily  to  take  care 
of  expansion  and  contraction  a  torch  us- 
ing the  gas  with  ordinary  atmosphere  air 
is  best  adapted.  This  torch  is  constructed 
on  the  Bunsen  burner  principle  and  is  sold 
by  almost  all  manufacturers  of  welding  ap- 
paratus. A  torch  of  this  kind  gives  a  soft 
flame  of  not  too  concentrated  a  heat. 

If  the  pre-heating  is  entirely  or  mainly 
for  the  purpose  of  economy  in  the  use  of 
acetylene  and  oxygen,  then  the  gas  should 
be  burned  with  a  torch  using  compressed 
air.  When  used  with  compressed  air  a 
more  concentrated  flame  of  higher  tem- 
perature is  secured — just  the  thing  for 
work  of  this  character. 


88      OXY-ACETYLENE  WELDING  &  CUTTING. 

Torches  of  either  of  the  two  types  are 
made  in  different  sizes  and  the  consump- 
tion of  gas  will  range  from  100  to  200  cubic 
feet  per  hour.  At  $1.00  per  1000  cubic 
feet,  they  will  cost  from  lOc  to  20c  per 
hour. 


Fi.u".  S. 
Kerosene   Pre-Heating   Torch 


FEE-HEATING    FURNACES.  89 

KEROSENE  AND  GASOLINE  TORCHES. 

For  outside  or  portable  work  one  of  the 
above  torches  is  very  desirable.  They  are 
not  well  adapted  for  expansion  and  con- 
traction pre-heating,  their  field  being  large- 
ly that  of  heating  up  heavy  castings  in 
order  to  save  in  the  use  of  acetylene  and 
oxygen.  Compressed  air,  usually  obtained 
by  a  hand  pump,  is  used  with  either  fuel. 
The  kerosene  torch  will  be  found  to  be 
more  economical  fo  operate  and  will  give 
a  higher  temperature.  These  torches  are 
also  manufactured  and  sold  by  the  leading 
welding  manufacturers. 

FURNACES   FOR   PRE-HEATING. 

We  have  seen  the  different  fuels  that 
can  be  used  for  pre-heating  castings  pre- 
paratory to  welding.  Now  the  casting  is  not 
heated  out  in  the  open  for  the  reason  that 
there  would  be  too  great  a  loss  of  heat  and 
the  casting  would  be  subjected  to  the  di- 
rect influence  of  drafts.  It  has  been  found 
necessary  when  heating  the  casting  to  en- 
close it  in  either  a  temporary  or  a  perma- 
nent furnace.  There  are  a  few  who  advo- 
cate the  use  of  a  permanent  furnace,  but 
unless  this  work  is  all  of  the  same  size  the 
extra  outlay  for  such  a  furnace  is  a  use- 
loss  expense;  besides,  they  are  usually  ex- 
travagant with  fuel.  The  most  practical 


90       OXY-ACETYLENE  WELDING  &  CUTTING. 

and  economical  furnace  is  a  temporary  one 
built  from  loose  fire  brick,  whether  char- 
coal, gas  or  kerosene  fuel  is  used. 

The  bricks  are  simply  laid  one  upon  the 
other,  leaving  a  space  of  from  6  to  12  inches 
around  the  casting,  depending  upon  its  size. 
If  charcoal  is  used,  the  bricks  are  spaced 
near  the  bottom,  leaving  cracks  through 
which  the  air  which  feeds  the  fire  can  pass. 
The  top  is  covered  with  sheet  iron  or  as- 
bestos. If  gas  is  used  s'pacing  of  the  brick 
is  not  necessary,  the  only  openings  required 
being  those  through  which  the  gas  torches 
pass.  If  the  heating  is  to  take  care  of  ex- 
pansion and  contraction,  the  gas  torches 
should  not  be  turned  directly  on  the  cast- 
ing, but  should  be  made  to  impinge  direct- 
ly on  the  brick.  This  will  cause  the  flame 
to  whip  around  the  casting  and  thereby 
secure  a  more  even  heat.  If  the  primary 
object  of  the  heating  is  a  saving  of  acety- 
lene and  oxygen  then  the  pre-heating  torch 
can  play  directly  on  the  casting. 

EXPANSION  AND  CONTRACTION. 

All  metals  are  affected  by  heat.  The 
action  of  heat  produces  an  increase  in 
volume ;  that  is,  a  casting  when  heated  has 
greater  length,  breadth  and  thickness.  This 
is  called  expansion  and  as  a  general  prop- 
osition this  expansion  increases  progres- 
sively as  the  temperature  increases.  As 


EXPANSION.  91 

the  casting  cools  itfe  volume  begins  to  get 
less,  until  at  normal  temperature  it  usually 
assumes  its  original  size.  This  is  called 
contraction.  It  is  well  to  remember  that 
you  cannot  stop  a  casting  from  expanding 
when  it  is  heated.  This  force  is  irresist- 
ible; no  power  can  prevent  it.  Do  not 
attempt  to  prevent  a  casting  from  expand- 
ing by  means  of  clamps.  If  you  should  be 
so  foolish  as  to  try,  and  the  clamps  were 
strong  enough,  distortion  of  the  casting 
would  inevitably  result.  As  most  castings 
are  of  irregular  shape,  and  the  metal  usual- 
ly varies  in  thickness,  it  is  necessary  to  take 
some  precautions  in  heating  so  that  the 
heavy  parts  will  expand  in  the  same  ratio 
as  the  thin  parts.  If  this  is  not  done  either 
breaking  or  distortion  is  very  apt  to  occur. 
This  precaution  is  uniform  heating  and  in 
order  to  secure  a  uniform  heat  sloiv  heating 
is  necessary.  For  pre-heating  of  cylinders 
and  like  castings  in  order  to  take  care  of 
expansion,  remember  to  heat  slowly  and 
uniformly  and  of  course  to  take  care  of 
contraction  cool  slowly  and  uniformly.' 
That  is  the  "meat  in  the  cocoanut,"  heat- 
ing slowly  and  uniformly  and  cooling  slow- 
ly and  uniformly.  When  the  foundryman 
made  the  casting  it  was  poured  from  molten 
metal  possessing  the  same  temperature 
throughout  and  flowed  into  a  mold  where 


92      OXY-ACETYLENE  WELDING  &  CUTTING. 

it  was  entirely  protected  from  the  air  by 
the  sand,  which  permitted  an  even  and  uni- 
form cooling.  Welding  with  the  oxy-acety- 
lene  flame  is  simply  re-casting  and  the 
beginner  would  do  well  to  study  and  follow 
foundry  practice  in  a  number  of  instances. 
Unless  the  beginner  studies  and  thor- 
oughly understands  the  principles  of  ex- 
pansion and  contraction  and  applies  it  to 
the  work  at  hand  he  will  not  be  a  success, 
regardless  as  to  how*well  he  may  manipu- 
late the  torch.  In  the  majority  of  cases  it  is 
just  as  important  to  maintain  alignment 
as  it  is  to  make  a  good  weld.  If  the  welder 
ignores  expansion  and  contraction,  it  is  in- 
evitable that  one  of  three  things  will  hap- 
pen: 
1st  — The  casting  on  cooling  will  break  in 

or  near  the  weld. 
2nd — Distortion  of  the    work    destroying 

alignment. 

3rd — The  weld  may  not  break  and  distor- 
tion may  not  occur,  but  there  will 
be  a  strain  in  the  casting,  causing  the 
welded  portion,  or  near  it,  to  snap 
and  break  when  the  load  is  placed 
on  the  machine. 

A  good  way  to  illustrate  the  effects  of 
expansion  and  contraction  and  one  appar- 
ently popular  with  those  writing  on  the  sub- 
ject is  represented  by  Figures  9,  10,  11 


CONTRACTION. 


93 


and  12.  Figure  9  represents  a  bar 
which  is  broken  at  "A."  In  this  case 
the  weld  can  be  made  without  giv- 
ing any  attention  to  expansion  and  con- 
traction in  view  of  the  fact  that  the 
ends  "B"  are  free.  Of  course,  while 


I 


>7 

Fig.  9. 

being  welded  the  heat  will  expand  it,  but 
there  is  nothing  holding  it  and  it  can  in- 
crease its  length  as  well  as  its  breadth  and 
thickness,  and  when  it  cools  it  comes  back 
into  its  original  position.  Now  in  Figure 
10,  B  A  B  represents  the  same  bar,  except 


B 


Fig.  10. 

that  now  it  is  the  middle  member  of  a 
frame.  The  length,  breadth  and  thickness 
is  the  same,  the  break  is  the  same  as  is 
also  the  location.  The  only  difference  is 
that  the  ends  "B"  are  now  a  part  of  the 


94      OXY-ACETYLENE  WELDING  &  CUTTING. 

sides  C  B  D.  Let  us  assume  that  we  make 
the  weld  exactly  as  we  did  when  the  bar 
was  not  a  part  of  the  frame. 


1 

1 

1           f* 

B         \        t 

9 

\         1 

Fig.  11. 


No  difficulty  would  be  experienced  in 
making  the  weld,  but  upon  cooling  it  would 
probably  break.  However,  if  it  did  not 
break  and  we  sight  down  the  edge  C  B  D 

c       ^^       c 


JL 


Fig.  12. 


it  will  appear  to  be  "sway-backed"  and  if 
we  place  a  straight  edge  along  this  surface 
(Fig.  11)  we  can  easily  see  that  it  does  not 
touch  at  "B"  and  is  somewhat  concave. 


MELTING   POINTS    OF    METALS.  95 

Now  when  the  weld  at  "A"  cooled,  BAB 
became  shorter  by  reason  of  contraction 
and  being  stronger  than  C  B  D  it  pulled 
these  two  sides  in.  The  casting  is  not  only 
warped  and  out  of  alignment,  but  a  con- 
siderable strain  is  also  set  up.  It  must  be 
plain  that  considerable  power  was  required 
to  bend  C  B  D  and  this  tension  is  what  is 
known  as  the  strain.  The  proper  way  to 
make  this  weld  is  shown  in  Fig.  12. 

The  ends  "C"  and  "D"  are  heated  and 
expand  and  the  break  at  "A"  opens.  We 
can  now  proceed  to  make  the  weld  without 
fear  of  bad  results.  The  ends  "C"  "D" 
and  the  weld  "A"  all  cool  down  together, 
leaving  the  casting  in  alignment  and  with- 
out a  strain. 

This  is  perhaps  the  simplest  illustration 
that  could  be  given  of  expansion  and  con- 
traction. Each  case  must  be  studied.  Some 
experimenting  will  have  to  be  done  and 
some  failures  will  be  recorded.  A  good 
rule  to  follow  is — "  When  in  doubt  pre-heat 
the  entire  casting.'' 

MELTING  POINTS'  OF  METALS. 

While  it  is  not  necessary  to  know  the 
various  melting  points  of  metals  and  alloys 
in  order  to  do  good  welding,  such  informa- 
tion will  likely  prove  interesting  and  in- 
structive. 


96      OXY-ACETYLENE  WELDING  &  CUTTING. 

Melting  Melting 

Metal  Point  Metal  Point 

Platinum    3200°  F.  Silver    1750°  F. 

Soft    Steel 2700°  F.  Brass  1700°  F. 

Hard    Steel 2550°  F.  Bronze    1650°  F. 

Nickel 2500°  F.  Aluminum 1200°  F. 

Cast  Iron 2100°  F.  Zinc 850°  F. 

Red  Copper 1900°  F.  Tin 650°  F. 

Authorities  differ  considerably  as  to  the 
above  temperatures.  We  have  taken  the 
figures  of  several  and  arrived  at  a  mean 
temperature  which  should  be  sufficiently 
correct  for  comparative  purposes. 

REGULATION  OR  ADJUSTMENT  OF  THE  FLAME. 

Elsewhere  we  have  shown  how  to  as- 
semble the  welding  unit  and  how  to  light 


Fig.  13. 
Acetylene  Only  Burning-. 

the  torch.  The  next  and  one  of  the  most 
important  things  is  the  question  of  adjust- 
ment so  that  a  neutral  flame  will  be  ob- 
tained and  maintained.  The  acetylene 
should  be  lighted  and  as  the  acetylene  torch 
cock  is  slowly  opened,  it  will  be  seen  that 
the  flame  jumps  a  very  slight  distance 
away  from  the  end  of  the  tip  when  using 
a  small  size,  and  as  the  size  of  the  tip  in- 
creases this  space  increases  likewise,  until 


REGULATION   OF  FLAME.  97 

in  a  very  large  tip  the  flame  will  be  sepa- 
rated from  the  end  of  the  tip  by  possibly 
3/16  of  an  inch.  We  now  turn  on  the  oxy- 
gen by  slowly  opening  the  torch  cock.  The 
first  thing  we  notice  is  that  the  entire  flame 
assumes  a  more  brilliant  and  whiter  color. 
A  slight  increase  in  the  oxygen  and  we  see 
that  the  end  of  the  flame  commences  to 
take  on  a  yellowish  cast  and  the  white  sec- 
tion is  shortening.  A  further  increase  in 
the  amount  of  oxygen  tends  to  increase  the 


Fig.  14. 
Excess  of  Acetylene. 

amount  of  yellow  and  diminish  the  amount 
of  white.  We  have  now  what  is  known  as 
a  carbonizing  flame.  By  that  is  meant  that 
there  is  not  enough  oxygen.  The  white  por- 
tion has  what  is  commonly  called  a  "rag- 
ged" edge.  If  welding  is  done  with  this 
kind  of  a  flame  the  metal  is  almost  sure 
to  be  hard  and  difficult  to  machine.  We 
slowly  further  increase  the  amount  of  oxy- 
gen and  as  we  do  so,  we  can  see  the  white 
portion  drawing  within  itself  or  shorten- 
ing up.  When  the  last  straggling  edge  dis- 
appears and  the  white  cone  is  round  and 
well  defined,  it  is  then  we  have  the  much 


98      OXY-ACETYLENE  WELDING  &  CUTTING. 

talked  of  neutral  flame.  The  length  of  this 
small  white  cone  should  be  about  2l/2  times 
its  diameter.  This  is  the  proper  flame  for 
welding.  If  the  oxygen  is  further  increased 
the  white  cone  shortens,  becomes  more 
pointed  and  the  hissing  sound  of  the  gas 
escaping  is  materially  increased. 


Fig.  15. 
Correct  or  Neutral  Flame. 


This  is  what  is  called  an  oxidizing  flame. 
By  that  is  meant  too  much  oxygen  is  being 
furnished  and  the  work  is  sure  to  be 
burned. 


Fig.  16. 
Excess  of  Oxygen. 

The  beginner  should  practice  lighting 
his  torch  for  an  hour  or  more.  A  hun- 
dred times  he  should  light  his  torch,  adjust 
the  flame,  turn  off  the  gas  and  relight 
again,  until  he  is  absolutely  satisfied  that 
he  knows  what  a  neutral  flame  is  and  how 
to  procure  it. 

When  the  neutral  flame  is  once  secured 


HOW  TO  MAKE  A  WELD.  99 

it  does  not  follow  that  it  will  continue 
neutral  indefinitely.  On  the  contrary  it 
will  quite  likely  vary  somewhat.  This  will 
instantly  be  detected  by  the  experienced 
welder  by  its  effect  on  the  metal.  How- 
ever, this  treatise  is  intended  primarily  for 
the  beginner — the  neophyte — and  not  for 
the  experienced,  and  so  the  thing  to  do  is 
every  now  and  then  test  the  flame  by 
slightly  closing  the  oxygen  torch  valve 
until  the  flame  is  carbonizing,  and  then 
again  slowly  opening  it  up  until  a  neutral 
flame  is  obtained.  The  trade  speaks  of  the 
small,  blue-white  flame  as  the  "cone"  and 
of  the  outer  flame  as  the  "envelope."  It 
is  well  that  one  should  know  these  terms 
and  speak  of  them  properly. 

EXECUTION  OP  A  WELD. 

We  have  already  told  how  to  install  a 
welding  outfit,  how  to  light  and  regulate 
the  torch  and  how  to  set  up  or  prepare  the 
work.  The  next  thing  is  how  to  execute  a 
weld.  Whether  the  welder  sits  or  stands 
upright  is  of  no  importance. 

The  torch  is  held  firmly,  but  not  rigidly, 
and  a  steady  hand  is  of  prime  importance. 
Welding  should  progress  forward  in  a  di- 
rection away  from  the  operator.  The  angle 
at  which  the  torch  should  be  held  depends 
upon  the  thickness  of  the  metal,  but  for  the 


100    OXY-ACETYLENE  WELDING  &  CUTTING. 

average  class  of  work  a  slightly  inclined 
forward  position  is  the  one  that  will  be 
found  best.  For  light  sheet  metal  work 
where  no  filler  rod  is  nsed  the  angle  of 
inclination  becomes  less,  whereas  for  heavy 
work  the  torch  will  be  held  almost  per- 
pendicular to  the  work. 

In  welding  the  torch  should  not  be  di- 
rected upon  a  particular  spot  for  any  great 
length  of  time,  but  should  move  slightly 
so  that  the  flame  will  come  in  contact  with 
other  parts  in  the  immediate  vicinity.  This 
should  not  be  understood  to  mean  that  the 
torch  should  sweep  a  circle  whose  diameter 
is  one  or  two  inches.  Most  beginners  make 
this  mistake. 

The  torch  should  be  moved  not  more 
than  %  or  5/16  of  an  inch  at  a  time  for 
average  work — say  %"  or  ^"  in  thickness. 
A  circular  motion  for  metal  of  this  thick- 
ness is  not  essential,  but  it  is  well  to 
acquire  it.  For  sheet  metal  work  this 
circular  movement  is  very  desirable, 
producing  a  very  smooth  and  pretty 
weld.  However,  there  are  some  that  prefer 
an  oscillatory  movement,  the  torch  being 
pushed  like  a  pendulum  from  one  side  of 
the  sheet  to  the  other  while  advancing  in 
a  forward  direction.  So  far  we  have  not 
referred  to  the  welding  rod.  It  should  be 
held  in  the  free  hand.  Instead  of  using  a 


SIZE    FILpTv   TO   USE.  101 

straight  rod,  it  will  Jbe  found  itiore  'coii- 
venient  for  the  welder  to  use  a  rod  having 
an  angle  of  90  degrees.  In  steel  this  is 
formed  by  simply  bending  over  3  or  4 
inches  of  the  end  and  continuing  to  do  this 
as  the  rod  is  used  up.  For  cast  iron,  we 
hold  the  end  of  one  rod  in  the  middle  of 
another  and  "tack"  the  two  with  the  torch. 
The  size  of  the  welding  rod  is  important 
and  should  be  proportional  to  the  thickness 
of  the  metal  welded. 

The  following  table  will  be  a  fair  guide 
to  follow : 

Dia.  ofWeld'g 

Rod  for  Dia.  of  Weld'g 

Thickness                       Cast  Iron  Rod  for  Steel 

of  Metal  No.  12 

No.  16  to  1<8  Gauge  Gauge  Wire 

i/8  in.  to  1,4  in.                    i/8  in.  i/8  in. 

14  in.  to  &  in.                    &  in.  &  in. 

%  in.  to  1/2  in.                     ^  in.  -&  in. 

1/2  in.  to  %  in.                    %  in.  %  in. 

%  in.  to  %  in.                     &  in.  %  in. 

Most  beginners  make  the  fatal  mistake 
of  not  getting  the  metal  to  be  welded  hot 
enough  before  adding  the  filler  rod.  It  is 
a  good  plan  in  beginning  a  weld  to  forget 
that  you  have  a  filler  rod.  Get  the  casting 
hot  and  then  start  the  metal  to  flowing  to- 
gether at  tlie  bottom  of  the  bevel.  Not  un- 
til then  should  the  filler  be  used.  The 
edges  of  the  weld  and  the  filler  rod  must 


10$ ,  OXV-ArrKTTLENE  WELDING  &  CUTTING. 

melt  dt  the  same  time.    If  this  is  riot  done, 
the  weld  will  be  of  no  value. 

The  welding  rod  should  not  be  held  so 
that  as  the  metal  melts  it  falls  in  drops 
on  the  weld.  In  a  great  deal  of  work  the 
welding  rod  is  held  against  the  welded  por- 
tion practically  at  all  times.  Where  this 
is  not  done,  the  rod  is  held  so  that  the 
outer  flame  of  the  torch  or  the  envelope 
will  keep  it  hot,  so  that  when  the  moment 
arrives  for  adding  on  some  metal,  the  rod 
is  lowered  into  the  molten  metal.  By  this 
time  the  end  of  the  rod  should  be  melting, 
but  it  may  be  necessary  to  direct  the  torch 
against  the  rod.  A  small  amount  of  metal 
is  added  and  then  the  edges  of  this  added 
metal  should  be  melted  and  made  to  inti- 
mately incorporate  with  the  main  body  of 
metal.  A  very  important  thing  to  bear 
in  mind  is  the  distance  the  torch  should 
be  held  from  the  metal.  For  steel  welding 
the  end  of  the  white  cone  should  just  touch 
or  brush  the  metal.  For  cast-iron  it  should 
not  touch  the  metal  but  should  be  held 
about  3/16  of  an  inch  from  it.  Sometimes, 
in  order  to  work  out  blow-holes  that  are 
the  result  of  impurities  burning  to  a  gas, 
it  may  be  necessary  to  push  the  end  of  the 
white  cone  down  into  the  molten  metal 
and  with  a  slight  rotary  motion  flirt  out 
the  impurities. 


CHAPTER  VI. 

WELDING  OF  DIFFERENT  METALS. 
CAST-IRON  WELDING. 

Probably  75%  of  the  welding  done  in  a 
custom  repair  shop  is  the  welding  of  cast- 
iron.  Contrary  to  popular  belief,  it  is  the 
easiest  welding  to  learn?  and  when  care  and 
good  workmanship  are  exercised  the 
welded  portion  will  be  superior  to  the  rest 
of  the  casting.  The  failures  that  occur  are 
usually  on  pieces  such  as  cast-iron  boiler 
sections  where  the  life  of  the  metal  has 
been  burned  out  on  account  of  long  contact 
with  a  fire,  or  on  work  where  expansion  and 
contraction  are  difficult  to  take  care  of. 

Cast-iron  is  an  alloy  of  steel  and  carbon. 
The  carbon  contents  vary  from  3%  to  5%, 
and  it  exists  in  two  states :  first,  as  a  chemi- 
cal mixture  and,  second,  in  a  free  state. 
In  the  latter  case  the  carbon  is  distributed 
throughout  the  iron  in  much  the  same  way 
that  salt  is  placed  in  bread.  Upon  the 
amount  of  free  carbon  in  the  cast-iron  will 
depend  the  softness  of  the  metal  and,  of 
course,  the  ease  with  which  it  can  be  ma- 
chined. 

HARD  SPOTS. 

The  bugbear  of  the  average  beginner  is 
hard  spots  in  cast-iron  welding.  By  ob- 

103 


104    OXY-ACETYLENE  WELDING  &  CUTTING. 

serving  a  few  rules  this  trouble  can  be 
practically  overcome.  The  important  rules 
to  be  remembered  and  observed  ar^e: 

First,  see  that  a  neutral  flame  is  main- 
tained at  all  times. 

Second,  keep  the  white  cone  about  *4  of 
an  inch  from  the  metal. 

Third,  use  a  clean,  high-grade  welding 
rod,  free  from  dirt  and  with  a  silicon  con- 
tent of  about  3%. 

Fourth,  use  only  enough  flux  to  make 
the  metal  flow  and  insist  on  a  flux  free 
from  carbonates. 

Fifth,  cool  the  work  slowly. 

Even  with  all  of  these  precautions  fol- 
lowed, occasionally  one  will  have  a  few 
ha^d  spots.  Usually  these  are  on  the  sur- 
face and  can  be  easily  removed  with  an 
emery,  but  if  any  difficulty  in  doing  this 
presents  itself  the  following,  which  was 
recommended  by  an  old  blacksmith,  may  be 
tried:  Place  some  powdered  sulphur  on 
the  weld  by  means  of  an  old  hack  saw  blade 
or  flat  file  and  rub  the  sulphur  on  the  weld 
until  the  suphur  ceases  to  burn  and  be- 
comes gummy ;  then  cool  slowly.  While  we 
know  there  are  some  objections  to  this, 
still  it  has  been  tried  by  the  writer  and 
while  not  infallible,  it  frequently  helps. 

It  is  necessary  to  weld  cast-iron  in  a 
horizontal  position.  This  is  because  it  has 


HARD   SPOTS.  105 

no  tenacity  when  molten.  Sometimes  it 
becomes  necessary  to  make  a  vertical  weld, 
in  which  case  a  heavy  piece  of  steel  or  a 
fire  brick  is  used  to  form  a  shelf.  As  the 
welding  progresses,  the  shelf  is  raised  or 
built  up  higher.  As  previously  stated,  the 
edges  of  the  metal  at  the  weld  should  be 
beveled  except  for  very  thin  metal. 

Only  first-class  welding  rods  should  be 
used.  These  should  be  purchased  from 
those  specializing  in  oxy-acetylene  appara- 
tus and  who  guarantee  to  flame-test  their 
welding  materials.  It  is  to  be  deplored 
that  at  the  present  time  there  seems  to  be 
a  tendency  to  buy  on  a  price  rather  than 
a  quality  basis.  It  is  the  very  poorest 
economy  to  buy  cheap  welding  materials. 

In  using  the  flux,  the  welding  rod  is 
heated  and  dipped  into  the  can  when 
enough  should  adhere  to  the  rod.  If  the 
iron  is  unusually  "dirty,"  it  may  be  found 
advisable  to  sprinkle  some  flux  on  the  weld 
with  the  fingers,  but  too  much  should  not 
be  used. 

Sometimes  the  operator  has  trouble  pre- 
venting the  metal  from  running  away  when 
trying  to  square  up  a  casting.  In  cases 
of  this  kind,  the  torch  should  be  turned 
over  so  that  the  flame  will  be  pointed  up. 
The  force  or  blast  of  the  flame  will  help 
to  hold  the  metal  and  prevent  its  running 


106    OXY-ACETYLENE  WELDING  &  CUTTING. 

away.  But  this  alone  will  not  do.  By 
watching  the  metal  closely  one  can  see  when 
it  is  about  ready  to  topple  over  and  run 
down  and  just  before  this  happens  lift 
the  torch  and  give  the  metal  a  chance  to 
set.  Then  go  back  and  add  a  few  more 
drops  and  in  a  very  short  time  enough 
metal  has  been  added  and  the  edge  is 
squared  up.  All  that  is  necessary  is  pa- 
tience and  practice. 

BLOW  HOLES. 

One  source  of  considerable  annoyance  to 
the  beginner  is  the  formation  of  blow- 
holes in  the  weld.  These  could  just  as  well 
be  called  gas  holes,  as  they  are  caused 
Cither  by  the  absorption  of  gases  or  by 
impurities  in  the  metal  burning  to  a  gas, 
probably  more  often  the  latter.  They  will 
form  with  the  good  wrelder  and  the  poor 
welder  alike,  but  the  difference  lies  in  the 
fact  that  the  good  welder  will  get  rid  of 
the  blow-holes,  whereas  the  inexperienced 
permits  them  to  remain  in  the  weld.  How 
does  the  good  welder  get  rid  of  them! 

Most  beginners  and  also  a  great  many 
who  have  had  considerable  experience  get 
the  surface  of  the  casting  flowing  a  little 
and  then  add  a  heavy  layer  of  cast-iron 
from  the  filler  and  then  attempt  to  "work 
in"  this  heavy  addition.  The  mistake  is 


BLOW-HOLES.  107 

flowing  iii  too  much  metal  at  one  time.  Not 
only  on  cast-iron,  but  on  any  kind  of  weld- 
ing never  add  any  more  metal  than  is 
necessary.  One  should  add  a  very  thin 
layer  at  a  time,  putting  it  in  the  right 
place  and  leaving  it  there.  A  slight  but 
constant  motion  of  the  filler  rod  and  the 
torch  should  be  maintained  until  the  weld 
is  finished.  The  filler  rod  should  be  dipped 
into  the  flux  quite  frequently  and  when  a 
thin  layer  is  added,  lift  the  torch  for  a 
second  or  two  and  allow  it  to  solidify  be- 
fore adding  any  more.  By  doing  this,  you 
allow  to  escape  the  gases  which  otherwise, 
as  in  case  of  a  heavy  addition  of  filler,  are 
covered  over  and  enclosed  and  are  unable 
to  break  through  the  heavy  layer  of  metal. 

In  the  making  of  bread,  lightness  is  de- 
sired. This  lightness  or  porosity  is  ob- 
tained by  the  formation  of  gas,  and  its  re- 
tention in  the  bread  until  -baked  or  solidi- 
fied, producing  a  multiplicity  of  blow-holes. 
If  for  any  reason  the  gas  escapes,  the  bread 
drops,  becomes  heavy  and  compact,  some- 
thing to  be  regretted  in  bakeries,  but  the 
very  thing  we  are  trying  to  do  with  the 
cast-iron — allow  the  gas  to  escape  so  that 
it  will  be  compact,  close-grained  and  free 
from  blow-holes. 

In  welding  of  large  castings  that  have 
had  to  be  pre-heated,  or  even  those  the 


108    OXY-ACETYLENE  WELDING  &  CUTTING. 

size  of  automobile  cylinders,  the  work  is 
attended  with  considerable  discomfort  on 
account  of  the  heat.  We  would  recommend 
the  nse  of  a  portable  electric  fan.  This 
can  be  set  on  a  box  and  pointed  so  that 
the  blast  of  air  is  in  an  upward  direction, 
just  in  front  of  the  welder.  It  is  needless 
to  say  that  the  current  of  air  should  be 
turned  so  that  it  will  not  strike  the  casting. 
By  using  a  fan  the  operator  will  at  all 
times  be  supplied  with  fresh  air  free  from 
any  fumes  and  will  be  kept  cool,  a  condi- 
tion that  enables  him  to  turn  out  more 
work  than  otherwise.  It  is  not  only  hu- 
mane, but  it  will  be  found  to  be  good  busi- 
ness practice  to  furnish  a  fan. 

WELDING    OF    STEEL. 

For  the  average  welder,  steel  may  be 
divided  into  two  classes — soft  steels  and 
hard  steels.  The  difference  between  these 
two  is  mainly  that  of  carbon  content.  In 
the  soft  steels  the  carbon  content  may  be 
as  IOAV  as  .05  per  cent,  while  extremely 
hard  steels  may  contain  as  much  as  1.5 
per  cent  of  carbon.  Low  carbon  or  soft 
steels  have  high  ductility  and  malleability. 

Increasing  the  carbon  contents  increases 
the  strength,  elastic  limit  and  the  property 
of  being  hardened  by  tempering.  The  soft 
steels  are  the  easiest  welded,  while  the 


STEEL  WELDING.  109 

hard  steels,  particularly  if  the  metal  is 
over  one  inch  in  thickness,  are  the  most 
difficult.  Operators  quickly  learn  to  do 
beautiful  work  on  thin  sheets  of  soft  steels, 
but  they  are  lost  when  attempting  heavy 
work.  Unquestionably  the  welding  of 
medium  and  heavy  steel  is  the  most  diffi- 
cult to  learn. 

The  average  welder  does  not  get  his 
metal  hot  enough  or  he  gets  it  too  hot  and 
burns  it  or  oxidizes  it,  as  the  chemist  would 
say.  Of  course,  it  is  a  comparatively  easy 
matter  to  overcome  the  first  shortcoming 
by  increasing  the  size  of  the  welding  flame 
or  by  playing  the  flame  on  the  metal  for  a 
longer  time,  but  the  second  fault  of  burn- 
ing the  metal  is  not  so  easy  to  avoid.  It 
is  practically  impossible  to  prevent  this, 
using  a  torch  of  poor  design  supplying  an 
excess  of  oxygen  to  the  flame.  We  have 
already  emphasized  the  importance  of 
using  scientifically  designed  torches,  but 
it  will  bear  repetition.  As  oxygen  is  always 
present  in  the  air,  this  atmospheric  oxygen 
will  greedily  attack  the  steel  when  in  a 
heated  condition.  All  of  us  are  familiar 
with  the  scale  that  forms  on  steel  when 
heated  in  an  open  fire.  This  scale  is  simply 
oxidized  iron  or  burnt  metal.  If  this  oxide 
is  allowed  to  incorporate  itself  with  the 
weld,  the  strength  is  bound  to  suffer. 


110    OXY-ACETYLENE  WELDING  &  CUTTING. 

It  would  almost  seem  superfluous  to 
again  impress  upon  the  beginner  the  im- 
portance of  flame  regulation,  did  not  ne- 
cessity demand  it.  An  excess  of  acetylene 
carbonizes  the  metal,  while  an  excess  of 
oxygen  burns  it. 

The  importance  of  using  a  good  welding- 
wire  is  usually  underestimated.  Swedish 
wire  has  long  been  advocated  and  it  is 
excellent,  but  we  doubt  at  the  present  time 
whether  there  is  any  genuine  wire  of  this 
kind  in  this  country.  This  does  not  mean 
that  excellent  domestic  welding  wi  re  is  not 
to  be  had.  On  the  contrary  our  country 
produces  as  fine  welding  wire  as  any  na- 
tion. The  impression  prevailed  for  a  long 
time  that  Swedish  iron's  reputation  was 
based  on  the  fact  that  it  was  made  with 
high-grade  charcoal,  but  recent  investiga- 
tions have  exploded  this  belief.  We  know 
now  that  the  strength  and  tenacity  of 
Swedish  iron  is  due  to  the  fact  that  cen- 
turies ago  Mother  Nature  deposited  with 
the  iron  ore  a  small  percentage  of  vanadi- 
um, and  when  the  ore  was  smelted,  this 
vanadium,  scavenger  like,  cleansed  the 
metal  of  its  impurities  and  thereby  im- 
parted those  properties  which  have  given 
it  its  reputation. 

Some  American  firms,  grasping  at  any- 
thing that  will  help  them  to  dispose  of  their 


STEEL  WELDING.  Ill 

wares  easily,  have  coined  trade  names  in 
which  a  part  of  the  name  Sweden  is  used, 
by  which  they  designate  their  wire.  Oft 
the  face  of  it,  it  is  designed  to  deceive  and 
mislead  the  public. 

Acting  on  the  knowledge  we  have  as  to 
the  properties  of  vanadium,  several  years 
ago  the  writer,  in  conjunction  with  one 
of  the  large  steel  companies,  experimented 
and  finally  produced  a  rod  containing  a 
low  percentage  of  vanadium  and  carbon 
which  for  heavy  welding  is  unsurpassed.  It 
must  be  remembered  that  there  are  many 
kinds  of  vanadium  steel  on  the  market  and 
only  one  kind  is  suitable  for  a  filler  rod. 

There  are  some  writers  who  advocate  the 
hammering  of  the  metal  after  welding. 
This  probably  does  do  some  good  if  the 
operator  is  able  to  determine  the  correct 
temperature  at  which  the  metal  should  be 
and  is  capable  of  maintaining  this  tem- 
perature, otherwise  more  harm  than  good 
will  be  done. 

The  exact  temperature  at  which  ham- 
mering should  be  done  is  difficult  for  the 
novice  to  either  determine  or  obtain,  and 
our  advice  is  to  learn  to  rely  upon  the 
welding  alone. 

The  welding  of  hard  steels  is  difficult 
even  for  an  experienced  welder  and  the 
beginner  had  better  not  try' this  class  of 


112    OXY-ACETYLENE  WELDING  &  CUTTING. 

work.  The  work  is  best  done  if  the  entire 
piece  or  at  least  a  considerable  portion  of 
it  is  pre-heated  to  a  cherry  red  and  a  tip 
selected  that  is  one  size  larger  than  if  the 
work  was  soft  steel.  If  anything,  the  flame 
should  be  slightly  carbonizing.  The  weld- 
ing should  be  done  fast.  One  should  not 
linger  over  the  work,  as  this  will  burn  the 
metal. 

WELDING  OF  BRASS  OR  BRONZE. 

Brass  is  an  alloy  of  copper  and  zinc, 
while  bronze  is  an  alloy  of  copper  and  tin. 
With  the  exception  of  the  cheap  brasses, 
that  is,  those  having  a  high  percentage  of 
zinc,  either  brass  or  bronze  can  be  welded 
with  good  success.  When  hot,  considerable 
care  should  be  exercised,  if  it  is  necessary 
to  move  the  work,  as  neither  one  of  the 
two  alloys  has  much  strength  then  and  the 
least  strain  will  cause  the  casting  to  break. 

The  work  should  be  beveled  and  the 
edges  and  immediate  vicinity  of  the  weld 
thoroughly  cleaned. 

A  welding  tip  one  size  larger  than  is 
necessary  for  the  same  size  work  in  cast- 
iron  should  be  employed.  Pre-heating  is 
justified  on  the  grounds  of  economy.  The 
white  cone  should  be  held  a  distance  of 
about  i/i"  from  the  metal.  Just  back  of 
the  weld  on  both  sides  should  be  heated 


BKASS    WELDING.  113 

thoroughly,  and  some  flux  sprinkled  in  the 
groove.  The  torch  is  then  switched  to 
the  beveled  edges  and  as  the  edges  com- 
mence to  melt  add  the  filler  rod  of  either 
Tobin  or  manganese  bronze,  first  dipping 
the  heated  rod  in  the  flux.  If  the  weld  is 
a  tooth  in  a  gear  or  located  at  some  wear- 
ing point,  manganese  bronze  is  preferable 
as  it  is  somewhat  harder,  otherwise  use 
Tobin  bronze. 

Weld  fast  or  you  will  find  blow-holes  in 
your  work  due  to  the  zinc  and  tin  burning 
out  and  the  metal  absorbing  gases. 

WELDING  OF  COPPER. 

The  melting  point  of  copper  is  not  only 
high,  but  it  also  conducts  the  heat  very 
rapidly  and  these  two  properties  combine 
to  make  it  a  metal  very  difficult  to  weld 
properly.  In  addition  it  absorbs  gases 
from  the  welding  flame,  which  causes  the 
formation  of  blow-holes. 

The  metal  should  be  cleaned  in  the  im- 
mediate vicinity  of  the  weld  and  the  edges 
to  be  welded  should  be  beveled.  A  welding 
tip  one  size  larger  than  is  required  for  the 
same  thickness  of  cast-iron  should  be  used. 
On  account  of  the  high  conductivity,  it  be- 
comes necessary  to  pre-heat  a  consider- 
able area  in  the  vicinity  of  the  weld  to  a 
high  temperature  before  starting  to  weld. 


114    OXY-ACETYLENE  WELDING  &  CUTTING. 

A  neutral  flame  should  be  maintained  and 
the  white  cone  should  be  held  about  1A  of 
an  inch  from  the  metal.  A  flux  should  be 
used.  While  a  pure  copper  rod  is  much 
used,  better  results  can  be  obtained  with 
a  special  rod  containing  a  very  slight  per- 
centage of  phosphorus. 

WELDING   OP   ALUMINUM. 

Of  late  years,  aluminum  has  come  into 
such  common  use  that  everyone  is  familiar 
with  it.  When  heated  to  a  high  tempera- 
ture it  becomes  very  fragile,  not  having 
sufficient  strength  to  hold  up  its  own 
weight.  Like  copper,  its  conductivity  is 
high.  Its  tendency  to  oxidize  is  greater 
than  that  of  any  other  commercial  metal. 

When  the  metal  is  heated  to  the  melting 
point,  this  oxide  is  easily  seen  and  by  the 
workman  is  usually  spoken  of  as  the 
' '  skin." 

The  piece  to  be  welded  is  prepared  in 
much  the  same  manner  as  though  it  were 
cast-iron  or  brass.  The  piece  is  cleaned 
and  the  edges  are  beveled.  For  the  begin- 
ner we  have  one  suggestion  to  make  which 
he  will  find  of  considerable  assistance,  but 
which  he  may  possibly  discard  after  he 
becomes  proficient.  We  have  already 
stated  that  the  metal  has  no  strength  when 
it  is  around  the  melting  point  and  the  be- 


ALUMINUM    WELDING.  115 

ginner  will  very  likely  find  his  work  sink- 
ing in  or  holes  dropping  through  it. 

When  this  happens  a  few  times  the  op- 
erator is  apt  to  become  "rattled"  and  dis- 
couraged. To  avoid  this  happening  one 
can  prepare  the  work  as  follows : 

After  the  work  has  been  cleaned  and 
beveled,  wet  some  paper  and  lay  over  the 
crack  on  the  underside.  Take  a  wire  and 
form  a  slight  loop.  Fasten  one  end  to  the 
casting  on  one  side  of  the  crack  and  the 
other  end  to  a  part  of  the  casting  on  the 
other  side  of  the  crack.  Take  some  plaster 
of  Paris  and  add  sufficient  water  until  it 
is  of  a  thick  consistency  and  then  put  it 
on  top  of  the  wet  paper  and  around  that 
part  of  the  casting  where  the  crack  is  lo- 
cated. The  wire  mentioned  above  will  act 
as  an  anchor  to  hold  the  plaster  of  Paris 
and  prevent  its  falling  out.  The  plaster 
miist  then  be  allowed  to  dry.  When  it 
has  done  so,  a  perfect  supporting  mould 
will  have  been  formed.  The  wet  paper  has 
prevented  any  of  the  plaster  from  getting 
into  the  crack.  We  can  now  proceed  to 
weld  without  the  danger  of  the  casting 
dropping  in  the  event  it  should  happen  to 
get  a  little  too  hot. 

The  average  beginner  is  apt  to  consider 
aluminum  welding  as  very  difficult.  This 
is  not  the  case  when  one  understands  the 


116  OXY- ACETYLENE,  WELDING  &  CUTTING. 

nature  of  the  metal  and  also  keeps  in  mind 
the  principles  of  expansion  and  contrac- 
tion. 

Compared  with  cast-iron,  what  do  we 
find?  That  it  melts  at  a  very  much  lower 
point  and  yet  conducts  heat  very  much 
more.  When  heated,  its  expansion  is  great- 
er and,  of  course,  when  cooling  its  contrac- 
tion is  greater  than  cast-iron.  This  means 
that  the  portion  that  is  brought  to  a  molten 
state  by  the  flame  will,  when  cool,  occupy 
less  space  than  will  cast-iron  under  the 
same  operation.  The  oxide  or  "skin" 
already  mentioned  requires  about  twice  as 
much  heat  to  melt  it  as  does  the  metal.  A 
little  reflection  and  we  see  that  some  ex- 
ternal means  must  be  resorted  to  in  order 
to  destroy  or  remove  this  oxide  before  a 
successful  weld  can  be  obtained. 

There  are  three  methods  of  doing  this. 
Each  is  good  when  properly  executed.  They 
are: 

First,  welding  by  puddling. 

Second,  welding  with  a  flux. 

Third,  combining  these  two  methods  by 
puddling  while  at  the  same  time  using  a 
flux. 

The  puddling  method  was  the  first  in 
vogue  and  is  still  used  quite  extensively. 
It  consists  in  removing  the  oxide  mechani- 
cally by  means  of  a  rod,  called  a  spoon. 


ALUMINUM    WELDING.  117 

Two  spoons  are  employed  and  they  are 
very  simple,  consisting » of  two  3/4"  steel 
rods,  each  flattened  at  one  end  and  one  of 
them  being  bent  at  a  right  angle.  The 
right  angle  spoon  is  used  to  scrape  out 
the  weld,  while  the  straight  spoon  is  for 
working  into  shape  the  new  material  that 
has  been  added  into  the  weld. 

In  practice  an  operator  starts  heating 
the  metal  and  when  he  thinks  it  is  about 
the  melting  point  he  tries  it  with  the  right 
angle  spoon.  If  it  is,  the  skin  or  oxide  and 
any  dirt  that  may  be  present  is  carefully 
scraped  out  for  a  distance  of  an  inch  or 
two.  The  spoon  is  then  dropped  and  the 
filler  rod  is  quickly  taken  up  and  material 
added. 

The  straight  spoon  is  then  substituted  for 
the  filler  and  the  metal  is  worked  and 
shaped.  When  this  is  finished  another 
inch  or  two  is  started  and  continued  until 
the  entire  crack  is  welded. 

Welding  aluminum  by  means  of  a  flux  is 
a  more  recent  method.  The  aluminum  is 
heated  to  the  melting  point,  as  is  likewise 
the  filler  rod,  when  the  latter  is  dipped  into 
the  flux  and  is  then  brought  into  contact 
with  the  molten  metal  at  the  weld.  When 
the  weld  is  cold,  the  flux  should  be  washed 
off  with  water  and  a  brush. 

Either  of  these  methods  is  good.     The 


118    OXY-ACETYLENE  WELDING  &  CUTTING. 

first  has  the  advantage  of  looks,  while  the 
latter  that  of  speed;  the  strength  of  each 
is  about  the  same.  The  third  method  is 
rather  fancied  by  the  writer  for  repair 
work.  It  is  really  a  combining  of  the  two 
above-mentioned  methods. 

The  spoon  is  used  to  clean  out  the  weld. 
The  flux  method  is  then  used,  and  when  a 
fewT  inches  of  welding  is  done,  we  revert 
back  to  the  puddling  method  and  use  the 
flat  spoon  for  shaping  and  finishing  up  the 
work. 

WELDING  MALLEABLE  IRON. 

Malleable  iron  is  practically  cast-iron 
that  has  been  annealed.  If  it  is  a  thin  cast- 
ing this  heat  treatment  tends  to  transform 
the  entire  piece  into  a  semi-steel,  but  if  the 
casting  is  fairly  thick  we  may  expect  only 
the  outer  portion  to  have  been  affected. 

Beginners  usually  experience  consider- 
able difficulty  in  detecting  a  piece  of  malle- 
able. Occasionally  an  experienced  man  will 
be  fooled.  If  the  casting  is  not  very  thick 
the  color  of  the  metal  at  the  break  will  be 
white  in  the  center  with  a  very  narrow 
dark  ring  around  the  outside.  If  the  cast- 
ing is  fairly  thick,  the  center  portion  will 
appear  cindery.  When  the  torch  is  ap- 
plied it  is  comparatively  easy  to  recognize 
it,  When  first  heated  it  sparks  a  little,  so 
that  vou  know  it  is  not  cast-iron.  When 


MALLEABLE   IRON   WELDING.  119 

it  commences  to  melt,  blow-holes  invari- 
ably form.  Some  still  cling  to  the  notion 
that  it  can  be  successfully  welded  with 
steel  or  with  cast-iron.  This  is  not  true. 
Whenever  steel  or  cast-iron  is  used  on 
malleable  it  shows  a  lack  of  knowledge  of 
the  business.  Whenever  it  becomes  neces- 
sary to  melt  malleable  iron,  upon  cooling 
it  will  be  converted  into  a  very  poor  grade 
of  cast-iron. 

The  only  successful  method  of  joining 
two  broken  pieces  of  malleable  is  by  braz- 
ing. This  has  been  proven  to  be  entirely 
satisfactory  from  a  standpoint  of  strength, 
if  the  work  is  properly  carried  out.  The 
Avork  should  be  cleaned  and  beveled.  Tobin 
bronze  or  high-grade  brazing  wire  is  used 
in  conjunction  with  a  flux.  The  malleable 
iron  should  not  be  heated  to  the  melting 
point,  a  bright  red  or  at  the  most  a  white 
heat  being  employed.  To  start  the  braze, 
the  writer  prefers  the  use  of  spelter,  which 
in  this  part  of  the  country  is  the  name  for 
fine  particles  of  brass  mixed  with  a  flux. 
This  is  sprinkled  on  the  beveled  edges  and 
coats  the  edges  with  a  thin  layer  of  brass. 
We  then  take  "the  Tobin  bronze  rod  and 
finish  by  using  it  as  filler,  using  it  rapidly. 

WELDING  OF  LEAD  OR  LEAD  BURNING. 

Lead  burning,  as  it  is  commonly  called, 


120    OXY-ACETYLENE  WELDING  &  CUTTING. 

is  really  the  first  form  of  autogenous  weld- 
ing. As  the  melting  point  is  low,  a  tip 
which  gives  an  exceedingly  small  flame  is 
used.  The  edges  to  be  welded  should  be 
cleaned  and  scraped  until  bright.  Since  the 
electric  starter  and  electric  lights  are 
almost  universally  used  on  automobiles,  a 
lead  burning  outfit  is  now  almost  a  neces- 
sity for  the  garage  in  the  repair  of  bat- 
teries. 

While  excellent  work  is  done  with  oxy- 
acetylene,  ordinary  coal  gas  and  oxygen 
is  used  with  splendid  results.  In  some 
cases  the  coal  gas  is  compressed  into  tanks, 
but  in  the  majority  of  cases  a  special  de- 
signed torch  is  used  which  permits  of  tak- 
ing the  coal  gas  direct  from  the  city  main 
at  a  pressure  of  only  a  few  ounces.  Very 
little  skill  is  required  for  average  work. 
Ordinary  clean  lead  cut  into  strips  from 
a  sheet  or  just  scraps  is  used  as  a  filler. 

For  lead  burning  of  chemical  tanks  or 
containers  it  is  sometimes  necessary  to  do 
vertical  work.  This  .requires  considerable 
practice.  It  may  be  well  to  state,  how- 
ever, that  a  vertical  weld  is  never  so  good 
as  a  horizontal  one  and  the  natural  infer- 
ence is  that  whenever  it  is  possible  in  work 
of  this  character,  the  tank  should  be  laid 
on  its  side  so  that  the  work  can  be  done  in 
a  horizontal  position. 


CHAPTER  VII. 

WELDING  OF  SHEET  METAL  AND  PIPE. 

WELDING  OF  SHEET  IRON. 
For  the  welding  of  very  thin  sheet  iron, 
say  from  No.  22  gauge  to  No.  28  gauge, 
it  is  rather  difficult  to  make  a  butt  weld, 
for  the  reason  that  almost  as  soon  as  the 
metal  is  in  a  molten  state,  a  hole  has  burned 


Fig.  17. 

This  shows  a  butt  weld,  with  edges  beveled  on  one 
side.  For  metal  of  l/s  inch  in  thickness  or  less  it  is 
not  necessary  or  desirable  to  bevel.  The  dotted  line  in- 
dicates the  metal  which  has  been  added  from  the  filler 
rod. 

through  which  is  difficult  to  patch.  It  will 
be  found  best  to  turn  up  the  edges  so  that 
a  flange  of  as  low  a  height  as  possible  is 
secured.  Clamps  should  be  used  to  hold 
the  metal  even  and  the  flange  should  be 


Fig.  18. 

This  shows  a  butt  weld  on  metal  %  inch  in  thickness 
or  more.  In  this  case  the  bevel  is  from  both  sides. 
This  is  desirable  if  both  sides  are  accessible. 

"spotted"  or  "tacked"    at    intervals    of 

about  four  or  five  inches.    No  filler  rod  is 

used,  as  the  flanges  upon  being  melted  down 

121 


122    OXY-ACETYLENE  WELDING  &  CUTTING. 

supply  the  necessary  material.  Some  knowl- 
edge of  sheet  iron  work  is  necessary  in 
order  to  properly  make  the  flange. 

For  sheet  iron  of  slightly  greater  thick- 
ness, say  Nos.  12,  14,  16,  18  and  20  gange, 
the  welds  can  be  made  in  several  ways.  It 
can  be  done  by  means  of  a  flange  as  indi- 
cated above  for  very  light  metal ;  it  can  be 
butt  welded  either  with  or  without  a  filler 
rod  or  it  can  be  welded  with  a  flange  dif- 
fering somewhat  from  that  mentioned 
above. 


Fig.  19. 

This  illustrates  two  lap-welded  joints,  one  in  which  the 
weld  is  made  only  from  one  side  and  the  other  where 
it  was  made  from  both  sides.  Ordinarily  this  is  not  a 
desirable  way  to  make  a  weld  with  the  torch,  but  occa- 
sion will  sometimes  demand  it. 

The  above  applies  to  the  welding  of  ir- 
regular shapes  and  small  articles.  If  the 
welding  is  on  sheets  formed  as  tanks  or 
containers,  and  the  task  is  a  quantity 
proposition,  more  detailed  information  is 
necessary.  As  previously  stated,  when 
welding  No.  20  gauge  metal  or  higher  it  is 
better  to  flange  the  edge.  On  this  light 
metal  it  is  difficult  to  make  the  flange  cor- 
rectly; in  fact,  it  cannot  be  done  in  a  ma- 
chine, owing  to  a  tendency  of  the  metal  to 


SHEET    METAL    WELDING.  123 

draw.  The  most  satisfactory  method  is 
to  tightly  fasten  the  sheet  in  a  clamp,  al- 
lowing about  1/32  of  an  inch  to  extend  be- 
yond the  clamps,  and  then  turn  the  flanges 
with  a  coarse  file.  This  flange  will  be  at 
an  angle  of  about  45  degrees,  but  as  the 
metal  increases  in  thickness  the  flange  will 
be  straighter  until  in  No.  16  gauge  and 
heavier  it  will  be  almost  at  a  right  angle, 
and  it  will  be  found  to  be  easier  to  make. 


=00= 


Fig.  20. 

This  shows  sheet  metal  flanged  preparatory  to  welding 
and  also  the  appearance  of  the  sheet  after  the  weld 
has  been  executed.  It  is  to  be  noted  that  in  the  illustra- 
tion the  height  of  the  flange  is  little  more  than  the 
thickness  of  the  metal.  When  edges  are  prepared  in 
this  manner,  the  molten  metal  of  the  flange  flows  onto 
and  incorporates  with  the  metal  of  the  sheet  beyond 
the  knuckle  of  the  flange.  In  some  cases  the  flange 
is  made  quite  high — from  }4"  to  %" — and  of  course  just 
the  edges  are  melted  together. 

For  flanging  No.  20  gauge  and  heavier 
an  old  press,  working  on  the  same 
principle  as  a  square  shear,  can  be 
utilized.  It  will  have  one  sharp  and  one 
dull  die ;  the  dull  one  being  on  top  and  the 
sharp  one  on  the  bottom.  As  the  dull  die 
comes  down  it  forms  the  edge  or  flange. 
The  top  or  dull  die  is 'set  back,  leaving  a 
gap,  the  width  of  which  is  equal  to  the  thick- 
ness of  the  metal.  As  an  example,  for  No. 


124    OXY-ACETYLENE  WELDING  &  CUTTING. 

16  gauge  metal,  it  would  be  set  back  1/16 
of  an  inch.  Welds  made  with  the  metal 
formed  in  this  manner  are  to  be  preferred 
to  a  butt  weld  even  with  a  filler  added,  as 
the  weld  is  made  faster,  it  is  stronger  as 
considerably  more  metal  of  the  same  stock 
is  in  the  weld  and  in  numerous  tests  made 
with  the  same  metal,  operator,  etc.,  where 
all  factors  were  the  same,  there  were  less 
leakers. 


Fig.  21. 

This  shows  one  method  of  welding  in  the  heads  or 
bottoms  of  round  tanks  made  from  light  stock.  The 
edge  of  the  head  is  flanged  and  the  two  edges  are  fused 
together. 

Regardless  as  to  whether  the  weld  is  a 
flange  or  butt,  it  is  advisable  to  have 
clamps  or  what  the  trade  calls  stakes,  for 
holding  the  edges. 

Usually  an  old  railroad  rail  is  utilized 
for  the  mandrel  portion  of  the  stake.  The 
ball  or  top  is  machined  so  that  the  sheets 
will  be  level.  In  the  middle  of  the  top  a 
longitudinal  slot  is  cut  about  ^-ineh  wide 
and  ^-inch  deep.  The  edges  of  the  sheet 
are  placed  directly  over  this  slot,  its  object 


.WELDING   CLAMPS. 


125 


being  to  prevent  the  heavy  rail  from  con- 
ducting the  heat  away.  Clamps  are  neces- 
sary to  hold  the  sheets  in  position  on  the 
mandrel.  They  are  made  of  two  pieces 
fastened  together  at  each  end  and  so  ar- 
ranged that  the  outer  end  can  be  lifted  to 
allow  of  the  introduction  and  removal  of 
the  sheets.  The  bottom  of  these  clamps  is 
machined  flat  and  the  inner  edge  of  each 
clamp  is  beveled  off  so  as  to  permit  of  the 
introduction  of  the  welding  flame.  The 
clamps  should  be  separated  about  one  inch. 


Fig.  22. 

This    is    the    same    edge    to    edge    welding    and    simply 
shows   how   the   ends   of   square   tanks   can   be   welded. 

This  depends  somewhat  on  the  thickness 
of  the  metal  being  welded,  widening  the 
clamps  for  the  heavier  metal  and  bringing 
them  closer  together  for  the  light  stock. 
For  a  butt  weld,  the  edges  should  be  put 
into  actual  contact  at  the  end  where  weld- 
ing is  started  and  they  should  be  separated 
at  the  other  end.  The  distance  of  separa- 
tion depends  upon  the  length  of  the  weld, 


126    OXY-ACETYLENE  WELDING  &  CUTTING. 

the  thickness  of  the  metal  and  the  speed 
of  the  operator.  No  hard  and  fast  rule  can 
be  given,  but  for  a  tank  34  inches  long 
made  of  No.  16  gauge  metal  it  is  usually 
spread  a/4  of  an  inch  and  for  No.  18  gauge 
metal  the  same  length,  it  is  spread  about 
3/16  of  an  inch. 


Fig.  23. 

This  shows  a  dished  and  flanged  head  of  a  round 
receptacle  in  position  and  partly  velded.  If  the  tank 
is  under  only  a  slight  pressure  the  weld  can  be  made 
at  the  knuckle  of  the  flange.  If  the  tank  is  for  high 
pressure  the  weld  should  be  made  farther  down  and 
nearer  the  edge  of  the  flange. 

Some  writers  have  fixed  2y2%  of  the 
running  length  of  the  weld  as  the  distance 
the  sheet  should  be  spread,  but  this  is  often 
erroneous.  As  the  weld  progresses,  the 
sheets  come  together. 

WELDING  OP  CONNECTIONS. 

In  almost  all  containers,  one  or  more  con- 
nections are  necessary.  A  pipe  nipple  is 
used,  and  for  the  sake  of  economy  is  usually 
cut  in  two  in  the  middle,  thus  making  two. 
It  is  then  put  in  a  lathe  and  a  cut  taken  on 
the  inside  threaded  portion,  leaving  a 
shoulder  about  %  of  an  inch  thick  and  3/16 


MACHINE  WELDING.  127 

of  an  inch  high.  The  hole  in  the  tank  is 
flanged  out  and  when  in  position  for  weld- 
ing we  have  the  edge  of  the  sheet  and  the 
thin  edge  or  shoulder  on  the  nipple  adja- 
cent. No  filler  is  used.  The  two  edges 
are  simply  melted  down  and  an  entirely 
satisfactory  connection  is  made.  (Fig.  27.) 


Fig.  24. 

This  shows  a  dished  head  without  a  flange  in  position 
and  partly  welded.  This  method  is  not  recommended 
where  the  container  is  subjected  to  high  pressures. 

MACHINE  WELDING  OF  SHEET  METAL. 

Machine  welding  can  be  employed  in  the 
manufacture  of  certain  articles  made  from 
rather  thin  sheet  metal.  Naturally,  in 
order  to  be  practical,  it,  must  be  a  repeat 
or  quantity  proposition.  These  machines 
are  either  automatic  or  semi-automatic. 
For  pipe  of  small  diameter,  wind  shield 
frames,  etc.,  the  metal  is  of  thin  gauge  and 
the  operation  consists  of  an  autogenous 
butt  weld  in  combination  with  pressure. 
This  last  is  important.  The  two  edges  to 
be  wrelded  are  mechanically  brought  to- 
gether so  that  they  are  even  and  in  per- 
fect alignment,  and  at  the  instant  the  oxy- 
acetylene  flame  produces  fusion  of  the 


128    OXY-ACETYLENE  WELDING  &  CUTTING. 

metal  on  top,  rollers  or  shives  engage  both 
sides  of  the  tube,  pressing  or  squeezing  the 
molten  edges  together.  In  practice  the  tube 
or  frame  is  formed  and  welded  in  one  op- 
eration. The  work  and  not  the  torch  moves. 
Strips  of  sheet  metal  are  cut  as  long  as 
desired,  care  being  taken  that  the  cut  is 


Fig.  25. 

This    shows    two    ways    of    welding1    fittings    or    connec- 
tions  in   tanks. 

even  and  the  width  of  the  "sheet  the  same 
throughout.  It  is  then  formed  by  being 
drawn  through  dies,  the  position  of  the  two 
edges  being  on  top  so  that  they  will  come 
under  the  flame.  As  the  tube  progresses 
towards  the  torch  it  is  guided  by  several 
pairs  of  shives  or  rollers,  one  set  of  which 
is  located  at  a  point  where  the  flame  touches 
the  metal. 

The  object  of  this  particular  set  of  shives 
is  twofold,  first  to  guide  the  tube  and  sec- 
ond to  press  in  on  the  sides  and  squeeze 
the  metal  together.  Other  sets  of  shives 
may  be  arranged  behind  the  flame  to 
straighten  the  tube  should  there  be  a  ten- 


TANK   WELDING.  129 

dency  towards  distortion.  At  the  present 
time  no  real  success  has  been  obtained  in 
an  effort  to  automatically  butt  weld  thin 
sheets  when  the  diameter  of  the  cylinder 
was  in  excess  of  12  inches.  On  the  other 
hand,  the  automatic  welding  of  thin  sheets 
is  entirely  practical,  regardless  as  to  the 
diameter,  if  the  edges  are  flanged.  This  is 
comparatively  simple  whether  the  vessel 
is  cylindrical  or  square.  Sometimes  the 
flanges  are  tacked  by  hand  at  two  or  three 


Fig.  26. 

For  divisions  in  tanks  or  where  top  or  bottom  is 
required  to  be  set  in  from  end  this  illustrates  a  very 
good  way.  The  weld  should  be  made  on  the  flange  near 
the  knuckle. 

points  before  the  actual  welding  begins.  In 
this  case,  the  torch  and  not  the  work 
travels.  The  torch  is  screw  driven  and 
some  experimenting  is  necessary  in  order 
to  determine  the  size  tip  necessary,  the 
angle  it  should  take,  and  the  speed  it  should 
travel.  For  boxes  and  some  cylinders  no 
clamping  or  supporting  devices  are  neces- 


130    OXY-ACETYLENE  WELDING  &  CUTTING. 

sary.  It  is  necessary  to  provide  some 
means  for  forcing  together  the  two  edges 
of  the  flange  immediately  in  front  of  the 
flame.  In  some  cases  this  is  done  by  means 
of  a  set  of  rollers  that  immediately  precede 
the  flame,  traveling  automatically  with 
the  torch;  in  others  this  is  done  by  an  op- 
erator using  a  pair  of  pliers  that  is  pro- 
vided with  a  couple  of  small  rollers. 

Most  automatic  machines  are  limited  as 
to  the  scope  of  work  which  they  will  ac- 
complish, but  for  the  particular  duty  for 
which  they  are  designed  they  will  do 
beautiful,  strong,  rapid  and  cheap  work. 


Fig.  27. 

In  some  instances  it  is  advisable  to  use 
a  water-cooled  tip,  but  for  most  work  this 
is  not  necessary.  The  necessity  for  a  water- 
cooled  tip  is  greater  where  low  pressure 
acetylene  is  used,  m  view  of  the  fact  that  a 
considerable  variance  in  the  flame  of  a  low 
pressure  torch  is  noted  upon  the  tip  be- 
coming heated.  On  the  other  hand,  where 
high  pressure  acetylene  is  used,  more  at- 
tention must  be  given  to  the  regulators 
to  see  that  they  are  operating  accurately. 


PIPE  WELDING.  131 

WELDING  OF  GAS,  AMMONIA,  AIR,  STEAM  AND 
WATER   PIPES   AND   MAINS. 

During  the  past  two  years,  the  o^y-acety- 
lene  torch  has  been  used  quite  extensively 
for  the  welding  of  pipes  and  mains. 


Fig.  28. 
This  shows  special  joint  on  gas  main  made  by  welding. 

In  the  West,  in  some  instances,  hundreds 
of  miles  of  pipe  have  been  laid  without  a 
threaded  connection,  while  in  many  cities 
this  class  of  welding  has  reached  consider- 
able proportions.  It  has  been  demon- 
strated that  the  strength  of  the  weld  can 
easily  be  made  greater  than  that  of  an  un- 
welded  pipe  and  the  cost  of  the  welded 
connection  is  less  than  the  cost  of  the 
screwed  connection.  There  is  also  no  dan- 
ger of  leakage.  Where  pipe  is  welded  a 
much  lighter  wall  is  permissible,  as  no 
allowance  need  be  made  in  its  thickness  for 
threading.  This  permits  of  a  considerable 
saving  and  at  least  one  company  is  now 


132    OXY-ACETYLENE  WELDING  &  CUTTING. 

advertising  a  pipe  having  extra  thin  walls 
for  welding.  By  specifying,  the  mills  will 
furnish  the  pipe  with  the  ends  beveled  at 
no  extra  cost.  In  practice  the  work  is 
done  as  follows : 


Fig.  29. 

This     shows    special     "Y"     joint    on    gas    mains    made 
by    welding. 

The  pipe  is  laid  end  to  end  on  top  of 
the  ground.  If  the  ground  is  uneven  it 
is  best  that  they  be  supported  by  2x4 's  in 
order  that  they  can  be  easily  turned.  If 
the  pipes  are  cut  at  a  bevel,  the  ends  are 
butted  together.  If,  however,  the  pipes  are 
cut  off  straight  a  space  of  from  1/16  to 


WELDING  GAS  MAINS. 


133 


i/i-inch  is  allowed  according  to  the  size  of 
the  pipe.  In  addition  to  the  welder,  two 
helpers  are  furnished.  They  are  stationed 
one  at  each  end  of  the  section  and  their 


Fig.  30. 

This    shows    reducer    made    en    gas    main    by    welding; 
flange   is  also  welded  on  to  pipe. 

duty  is  to  turn  the  pipe  with  tongs  as  the 
welding  progresses,  always  permitting  the 
operator  to  weld  on  top  of  the  pipe,  as 
greater  speed  can  be  made.  The  pipe 


134    OXY-ACETYLENE  WELDING  &  CUTTING. 

should  be  turned  towards  the  welder.    Hose 
of  sufficient  length  should  be  provided  so 


This  shows  a  spiral  coil  made  of  continuous  lengths 
of  pipe,  homogeneously  welded  and  bent  into  shape. 
These  coils  are  used  in  refrigerating  systems. 

that  he  may  weld  from  either  side  of  the 
pipe.    Ordinarily,  pipe  comes  in  about  20- 


WELDING   PIPE. 


135 


foot  lengths,  but  for  welding  purposes  it 
can  be  procured  in  40-foot  lengths,  thereby 
reducing  the  connections.  In  cities,  the 
number  of  lengths  that  can  be  welded  to- 


Fig.  32. 

This  shows  37  feet  of  pipe,  originally  in  two  pieces 
but  welded  together  in  the  center  and  bent  to  form 
an  expansion  loop.  The  weld  can  be  seen  just  above 
the  crane  hook. 

gether  is  usually  limited  by  the  length  of 
the  blocks,  but  in  the  country  quite  fre- 
quently lengths  of  1000  feet  or  more  are 


136    OXY-ACETYLENE  WELDING  &  CUTTING. 

welded   together   before   rolling   into   the 
trench. 

The  welding  of  two  sections  in  the  trench 
is  more  difficult.  This  weld  must  of  neces- 
sity be  a  stationary  one,  so  a  pit  must  be 
dug  of  sufficient  size  to  permit  the  operator 


Fig.  33. 

This  shows  a  welded  drip  composed  of  16-inch  pipe. 
This  not  only  makes  a  better  job  but  on  this  drip  there 
was  a  saving  of  $450.00  over  the  old  method. 

— Courtesy  of  National  Tube  Company. 

to  work  on  both  sides  and  under  the  pipe. 
The  welding  at  this  connection  consists  of 
!/4  horizontal,  y2  vertical  and  %  overhead, 
but  with  practice  this  is  easily  accom- 
plished. It  follows  that  all  sorts  of  tees, 
angles,  reducers  and  connections  can  be 
welded. 


STRENGTH    OF    WELDS.  137 

It  may  be  of  interest  to  give  the  result 
of  some  tests  showing  the  relative  strength 
of  welded  and  screwed  pipe  connections. 

Pipe  Size  Dia.  Welded  Connection  Screwed  Connection 

1/2  in.  12250  pounds  8560  pounds 

%   in.  21276  pounds  12640  pounds 

1       in.  29810  pounds  17560  pounds 

1V2  in.      •          44120  pounds  31440  pounds 


Fig.  34. 


This  gives   some   idea   of  the   appearance   of  a  cross   in 
an  8  inch  main  when  welded. 

The  cost  of  welding  depends  upon  the 
skill  of  the  welder,  the  efficiency  of  the 
apparatus  and  also  upon  local  conditions. 


138    OXY-ACETYLENE  WELDING  &  CUTTING. 

If  not  delayed  too  much  in  moving  from 
one  point  to  another,  a  competent  man  will 
weld  as  follows : 


10  to  12  joints  of 

5  to     6  joints  of 

3  to     4  joints  of 

2  to     3  joints  of 

1  joint     of 


2  inch  pipe  per  hour 

3  inch  pipe  per  hour 

4  inch  pipe  per  hour 
6  inch  pipe  per  hour 

8  inch  pipe  in  about  40  min. 


1  joint     of  12  inch  pipe  in  about     1  hour. 


Fig.  35. 

This  shows  a  3  inch  lateral  welded  to  an  8  inch  main; 
a  simple   operation   for   the   Oxy-acetylene   torch. 

A  comparison  of  the  cost  of  joints  of 
different  size  welded  and  with  threaded 
couplings  follows: 

Size  of  Pipe  1/2"     %"     1"      iy2"     2"       3"      4" 

Butt  Welded  Joints. $0.03     .04     .05     .07     .10     .18     .30 
Threaded  Couplings  $     .04     .05     .07     .11     .15     .32     .52 


COST  OF  WELDING.  139 

Attention  is  directed  to  the  fact  that  as 
the  pipe  sizes  increase,  the  advantage  of  a 
lower  cost  for  the  welded  joint  is  very 
much  greater. 

It  follows  that  the  welding  of  steam,  air 
and  water  pipes  in  industrial  plants,  rail- 
road shops,  yards,  etc.,  is  entirely  feasible 
and  in  a  great  many  instances  preferable 
to  threaded  connections.  As  an  example, 
the  Terminal  Kailroad  Association  of  St. 
Louis  have  welded  all  of  the  pipes  running 
through  their  yards.  The  St.  Louis  Re- 
frigerating &  Cold  Storage  Company 
welded  a  great  many  miles  of  their  street 
ammonia,  pipes  and  the  results  are  so 
satisfactory  that  they  are  replacing  the 
screwed  connections  with  welded  joints  as 
rapidly  as  possible. 


CHAPTER  VIII. 

WELDING  or  VARIOUS  PIECES. 

WELDING  OF  BOILERS. 

Probably  in  no  field  of  welding  has  ad- 
vancement been  faster  or  the  application 
greater  than  in  the  repair  of  boilers. 
Cracks,  patches  and  entire  sheets  are  now 
welded  with  complete  success.  Naturally, 
there  are  various  ways  of  doing  this  weld- 
ing, and  it  follows  that  practical  men  will 
frequently  conscientiously  differ  as  to 
which  method  is  the  best.  It  is  the  desire 
of  the  author  to  give  to  you  at  least  one 
way  of  doing  the  work  well.  If  you  can 
improve  over  it,  so  much  the  better. 

The  first  job  we  will  discuss  is  the  weld- 
ing of  a  half  side  sheet  in  a  locomotive  fire 
box.  With  the  exception  of  the  side  which 
is  to  be  welded  the  new  sheet  is  prepared 
exactly  as  though  it  were  to  be  riveted  in. 
When  possible,  all  stay  bolts  should  be  put 
in,  with  the  exception  of  a  row  on  each 
side  of  the  weld.  The  mud  ring  and  the 
door  and  flue  sheets  can  be  riveted  in, 
leaving  two  or  three  rivets  on  each  side 
of  the  weld  so  that  the  flange  can  be  raised 
up  to  allow  the  sheet  to  be  welded  un- 
derneath. 

If  the  front  and  flue  sheets  are  old  ones 

140 


BOILER  WELDING.  141 

this  can  be  omitted  and  tjie  flange  welded 
to  the  side  sheet  for  six  or  more  inches 
each  way.  The  rivets  should  be  put  in 
after  welding.  While  it  is  usually  more 
convenient  to  put  in  at  one  time  all  of 
the  stay  bolts  and  rivets,  with  the  excep- 
tions noted  above,  it  is  not  necessary,  and 
it  can  be  dispensed  with,  excepting  one 
row  of  stay  bolts  which  hold  the  edges  to- 
gether. No  bad  effects  will  follow,  the 
sheet  will  not  draw  up  a  bit  and  the  rivet 
holes  in  the. mud  ring  and  the  stay  bolt 
holes  will  line  up  perfectly.  Of  course,  the 
edges  of  the  new  and  the  old  sheet  where 
the  weld  is  to  be  made  are  beveled  so  that 
they  form  an  angle  of  90  degrees/  A  space 
or  opening  about  *4"  wide  is  allowed  be- 
tween the  two  sheets.  The  new  sheet  is 
cut  to  allow  for  this,  if  not  a  ripping  tool 
is  used  to  provide  it.  When  the  sheet  is 
properly  fitted  the  welding  is  begun.  It 
will  now  be  necessary  to  refer  to  Fig.  36, 
which  represents  a  side  sheet  ready  for 
welding.  The  edge  next  to  and  under  the 
flange  No.  1  is  first  welded.  We  then  move 
ahead  about  ten  inches  to  No.  2  and  weld 
back  to  No.  1,  then  go  to  No.  3  and  weld 
back  to  No.  2  and  so  on  across  the  sheet. 
It  is  sometimes  necessary  to  have  a  pinch 
bar  to  pull  the  edges  in  line;  otherwise, 
there  will  be  no  trouble  with  the  welding. 


142    OXY-ACETYLENE  WELDING  &  CUTTING. 

Dozens  of  sheets  have  been  welded  in 
this  way  without  any  trouble,  except  in 
the  case  of  a  green  man  who  was  not  able 
to  make  a  weld.  One  advantage  is,  the 
welder  can  stop  at  any  time  without  any 
trouble. 


0«    O         Oja 


o      cyr 


Fig.  36. 

There  are  two  other  methods  used  in 
welding  in  side  sheets,  which  the  writer 
does  not  like  so  well,  but  which  are  used 
by  others  with  from  fair  to  good  results. 

The  first  consists  in  dropping  one  end 
of  the  sheet  about  2%  of  the  running 
length.  This  was  perhaps  the  first  method 
used  in  this  country  and  some  still  cling  to 
it.  If  the  sheet  is  dropped  the  correct  dis- 
tance, it  will  pull  up  into  place  as  the  weld- 


BOILEB    WELDING.  > 

ing  progresses.  The  trouble,  however,  is 
due  to  the  fact  that  there  can  be  no  fixed 
rule  for  determining  how  much  the  sheet 
should  be  dropped  for  each  individual  weld- 
er. The  reason  is  that  this  distance  which 
the  sheet  is  dropped  is  determined  to  a 
very  considerable  extent  by  the  speed  of 
the  wilder,  and  no  two  men  weld  at  the 
same  speed. 

The  other  method  consists  in  putting  in 
the  new  sheet  as  though  it  were  to  be  riv- 
eted. The  stay  bolts  are  put  in  except  the 
two  or  three  rows  at  the  top  near  the  line 
of  the  weld.  Bolts  are  put  through  the 
outer  sheet  and  forced  against  the  new 
sheet.  This  shoves  the  new  sheet  away 
from  the  line  of  the  weld.  Another  bolt 
is  nearer  the  edge  to  be  welded  and  it 
extends  to  the  outer  sheet.  An  assistant 
on  the  outside  tightens  this  bolt  and  pulls 
the  new  sheet  back  into  position.  By  do- 
ing this  a  corrugation  or  hump  is  produced 
in  the  new  sheet  just  below  the  line  of  the 
weld.  The  welding  can  progress  from 
either  end,  and  as  it  does  the  bolts  should 
be  released,  with  the  result  that  the  con-<$> 
traction  pulls  the  corrugation  out,  leaving 
the  sheet  straight  and  in  good  shape. 

WELDING  OP  A  SIMPLE  CRACK. 

The  crack  is  prepared  by  being  beveled 


144   OXY-ACETYLENE  WELDING  &  CUTTING. 

to  the  usual  90  degree  angle.  A  y8-incli 
to  i/i-inch  opening  is  made  at  the  bottom, 
depending  upon  the  length  of  the  crack. 
Before  welding,  heat  in  the  line  of  the  weld 
for  several  inches  at  the  ends  of  the  crack. 
This  is  done  to  expand  the  solid  sheet  and 
open  the  crack.  If  the  crack  is  a  short  one 
of  only  a  few  inches,  start  at  one  end  and 
finish  up  at  the  other  and  then  lieat  a 
few  inches  beyond. 

If  the  crack  is  a  long  one,  say  18  inches 
or  more,  instead  of  starting  at  the  end, 
begin  about  8  inches  from  the  end,  and 
weld  back  in  exactly  the  same  manner  as 
indicated  for  welding  in  a  side  sheet. 

WELDING  OP  A  PATCH. 

In  the  welding  of  patches,  it  is  preferable 
to  use  a  triangular  patch,  with  the  corners 
slightly  rounding,  say  about  one  inch 
radius.  With  this  shape  of  patch  there 
can  be  no  parallel  welds  as  is  necessary 
with  any  other  shape,  and  this  is  to  be  de- 
sired; also  there  are  only  three  sides  or 
legs  to  weld.  Each  leg  of  the  patch  should 
be  straight.  The  bad  place  is  cut  out  with 
the  cutting  torch  and  the  patch  fitted  in, 
first  being  prepared  by  beveling,  etc.,  the 
same  as  was  done  in  the  case  of  the  side 
sheet  and  the  crack. 

By  referring  to  Figs.  37  and  38,  the  man- 


BOILER    WELDING. 


145 


nor  in  which  the  weld  is  made  will  be  easier 
understood. 

In  Fig.  ,37,  we  show  a  patch  in  the  form 
of  a  right  angle  triangle  and  in  Fig.  38  the 
patch  is  an  equilateral  triangle.  The  weld- 
ing differs  little  in  either.  The  welding 
is  started  at  No.  2  and  the  weld  is  made 
towards  No.  1,  then  we  go  to  No.  3  and 
weld  to  No.  2  and  from  No.  4  to  No.  3. 


Fig.  37. 

It  is  then  preferable  to  allow  the  weld  to 
cool  down,  and  then  before  starting  weld- 
ing heat  in  the  line  of  the  weld  No.  4  to 
No.  7  for  about  6  inches  at  each  end,  as 
shown  by  XX.  Then  start  welding  at  No. 
5  and  weld  to  No.  4,  jump  to  No.  6  and 
weld  to  No.  5  and  finish  this  leg  with  a  weld 
from  No.  7  to  No.  6.  Then  let  this  weld 


146    OXY-ACETYLENE  WELDING  &  CUTTING. 

cool  and  before  starting  on  the  final  leg 
heat  in  the  line  of  the  weld  No.  7  to  No.  1 
for  about  6  inches  as  shown  by  XXX.  In 
making  this  final  weld  it  is  better,  if  pos- 
sible, to  start  at  No.  10  and  weld  to  No.  1, 
then  at  No.  9  and  weld  to  No.  10  and  so  on 
until  completed.  By  doing  this  the  weld  is 
made  upwards,  which  is  faster  and  easier. 
Of  course,  conditions  are  sometimes  such 
that  this  is  not  desirable.  It  is  simply  a 
matter  of  convenience. 


Fig.  38. 

There  are  some  who  use  a  dished  patch 
and  others  one  with  the  edges  corrugated. 
Undoubtedly  patches  made  in  this  manner 
are  at  times  of  assistance  to  the  welder,  but 
the  writer  is  strongly  of  the  opinion  that 
this  is  not  necessary  if  the  welding  is  done 


BOILER    WELDING.  147 

properly.  An  examination  of  a  n umber  of 
welds  that  proved  defective,  showed  con- 
clusively in  nearly  every  instance  that 
either  the  welding  or  the  judgment  was 
poor,  or  both.  Any  boiler  sheet  should 
stand  the  shrinkage  of  one  welded  seam 
and  if  that  weld  is  allowed  to  cool  before 
the  next  weld  is  made  there  will  only  be 
the  shrinkage  of  one  weld  to  consider  when 
the  last  weld  is  made.  There  should  be 
very  little  strain  in  a  weld  when  cold. 
AYhenever  a  weld  cracks  immediately  after 
welding  while  it  is  still  hot,  an  indication 
that  the  weld  is  poorly  made,  it  will  be 
found  that  the  crack  opens  widely,  some- 
times as  much  as  %  of  an  inch. 

If  the  weld  is  properly  made  and  it 
should  crack,  which  will  only  happen  after 
it  becomes  cold,  it  will  be  found  to  show  as 
a  very  faint  line.  This  shows  that  in  cool- 
ing the  metal  in  the  good  weld  stretched 
considerably,  whereas  in  the  poor  weld 
there  was  not  sufficient  strength  to  permit 
of  the  metal  stretching. 

WELDING    CRACKS    IN    THE    THROAT 
SHEET  OF  BOILER. 

Cracks  often  form  at  the  throat  sheet. 
They  usually  begin  at  the  water  side.  A 
great  many  consider  it  impossible  to  suc- 
cessfully weld  cracks  of  this  kind,  and  yet 


148    OXY-ACETYLENE  WELDING  &  CUTTING. 

the  writer  knows  thoroughly  competent  op- 
erators who  are  doing  this  with  entire  satis- 
faction. The  work  must  be  carefully  done 
and  the  weld  reinforced  for  about  one  inch 
on  both  sides  of  the  line  of  the  weld  and  be- 
yond the  end  of  the  crack,  and  when  fin- 
ished, heated  in  the  same  line  for  some  dis- 
tance each  end  of  the  weld.  Where  pos- 
sible the  weld  should  be  made  on  both  the 
water  side  and  the  outside,  but  one  side 
alone  will  do. 

WELDING    OF    AUTOMOBILE    CYLINDER. 

The  welding  of  an  ordinary  crack  in  the 
water  jacket  of  an  automobile  cylinder  is 
not  a  difficult  task  if  one  has  a  fair  knowl- 
edge of  welding  and  carries  out  to  the  let- 
ter instructions  as  to  pre-heatirig.  The 
cylinder  should  always  be  stripped,  and  if 
possible  educate  your  customers  to  bring- 
ing them  to  the  shop  in  this  condition. 
Valves,  springs,  pet-cocks,  etc., -should  all 
be  removed.  The  cylinder  should  be  care- 
fully examined  in  a  good  light  to  determine 
if  possible  whether  there  are  airy  cracks 
other  than  those  which  are  easily  seen. 
Sometimes,  when  considerable  care  is  exer- 
cised, but  frequently  through  carelessness, 
the  operator  overlooks  a  crack  and  has  to 
reweld  the  cylinder.  The  cracks  should  be 
chipped  to  a  45-degree  angle  with  a  diamond 


CYLINDER   WELDING.  149 

point.  This  not  only  insures  a  better  weld, 
but  when  this  is  done  one  is  very  much  more 
apt  to  detect  stray  cracks  If  the  cylinder  is 
painted,  this  should  be  removed  for  about 
an  inch  on  both  sides  of  the  weld  by  means 
of  an  old  file.  Some  graphite  should  be 
obtained  and  mixed  with  kerosene  until  it 
is  of  a  thick,  pasty  consistency.  This 
should  be  rubbed  on  the  inside  of  the 
cylinders  and  on  the  valve  seats  and  also 
on  the  threads  of  the  valve  chambers  by 
means  of  a  swab,  which  is  simply  made  by 
tying  some  rags  or  waste  on  the  end  of 
an  iron  rod.  This  may  seem  unnecessary 
to  some,  but  it  certainly  will  protect  those 
parts  which  are  covered  with  it,  and  their 
appearance  after  the  welding  is  finished 
will  be  better.  This  will  please  the  custom- 
er, and  the  writer  believes  you  cannot  be 
far  wrong  when  you  do  that. 

Tike  cylinder  is  now  ready  for  pre-heat- 
ing.  Place  it  with  the  valve  parts  down 
and  the  open  end  of  the  cylinder  up.  Do 
not  lay  it  on  its  side.  Usually  there  is  an 
abundance  of  old  scrap  asbestos  around  a 
welding  shop,  and  some  think  it  advisable 
to  fill  the  cylinder  with  this.  Certainly  it 
can  do  no  harm,  and  it  may  do  good.  En- 
close the  cylinder  on  all  sides  with  fire 
brick;  this  makes  a  temporary  furnace.  If 
charcoal  is  used  it  should  be  lighted  and 


150    OXY-ACETYLENE  WELDING  &  CUTTING. 

allowed  to  burn  of  itself.  No  forced  draft 
should  ever  be  employed.  Remember  that 
what  is  desired  is  an  even  heat,  and  this  is 
best  obtained  by  slow  heating.  If  coal  gas 
is  employed,  a  torch  using  atmospheric  air 
should  be  used,  and  the  flame  made  to 
impinge  on  the  brick — not  on  the  cylinder. 
A  piece  of  sheet  iron  or  asbestos  paper  is 
laid  on  top  of  the  brick  furnace  to  keep  out 
any  drafts.  Some  use  a  metal  hood,  count- 
er-weighted, which  will  cover  the  entire 
furnace.  Occasionally  the  cylinder  should 
be  examined  as  to  its  condition.  The  de- 
gree to  which  it  should  be  heated  is  one 
of  the  things  on  which  there  is  a  difference 
of  opinion. 

Some  heat  to  a  point  where  it  is  just 
too  hot  to  lay  your  hand  on,  others  heat 
to  a  dull  red,  while  there  are  some  who 
raise  the  temperature  still  higher.  The 
writer's  experience  would  justify  hi^  ad- 
vising almost  a  dull  red  heat.  The  cylmder 
should  then  be  turned  in  a  position  for 
welding.  If  charcoal  is  used  it  is  left  in  the 
fire;  if  coal  gas  the  torch  is  either  turned 
low  or  extinguished  altogether.  For  turn- 
ing or  moving  the  cylinder,  d  small  chain 
block  with  an  old  pair  of  ice  tongs  will 
be  found  very  convenient,  eliminating  in 
many  instances  the  need  of  a  helper.  The 
welding  should  then  be  done.  If  it  is  a 


WELDING    OF    A    LUG.  151 

long  crack  or  several,  requiring  consider- 
able time,  it  is  best  to  stop  before  com- 
pletion and  reheat  by  the  addition  of  more 
charcoal  or  by  turning  on  the  gas  torches. 
When  finished,  again  turn  on  the  gas 
torches  for  a  while  or  replenish  the  char- 
coal, cover  well  and  let  it  cool  slowly. 

In  justice  to  yourself  and  your  customer, 
always  test  the  cylinder  under  water  pres- 
sure before  sending  it  out.  For  doing  this 
quickly  a  number  of  wooden  plugs  of  differ- 
ent sizes  should  always  be  kept  on  hand  for 
closing  openings  for  which  you  will  prob- 
ably have  no  plugs.  If  you  have  a  water 
system,  connect  the  water  line  with  one 
opening  and  turn  on  the  pressure.  If  ,not, 
fill  with  water  and  use  a  hand  pump,  rais- 
ing the  pressure  to  15  or  20  pounds. 

WELDING  OP  A  LUG  ON  A  MANIFOLD 
OR    A    CYLINDER 

Anyone  familiar  with  either  casting  will 
know  that  their  faces  are  machined  and, 
therefore,  true.  Naturally,  it  is  desirable 
that  this  alignment  be  maintained  when 
welding  on  a  lug  that  has  been  broken  off. 

If  one  possesses  a  face  plate  or  a  straight 
edge,  the  manifold  or  the  cylinder  can  be 
clamped  to  it,  first  plncinir  underneath  two 
or  three  thicknesses  of  ordinary  paper. 
Place  the  roken  lug  in  position  and  either 


152    OXY-ACETYLENE  WELDING  &  CUTTING. 

clamp  it  down  or  hold  in  place  with  a  two 
or  three-pound  weight.  Do  not  use  any 
paper  under  th.  broke;*  lug.  B\  doing  this, 
the  lug  will  be  slightly  lower  than  the  re- 
mainder of  the  casting  and  this  will  allow 
for  the  pull  or  shrinkage  in  the  metal.  Tack 
the  weld  at  one  side  and  then  start  at  the 
other  side  and  weld  around  to  where  the 
' ' tack"  was  made.  The  clamps  should  then 
be  removed  and  the  casting  turned  over 
and  the  weld  touched  up  from  this  side. 
After  the  weld  is  finished,  cover  with  as- 
bestos and  allow  to  cool.  If  there  should 
be  a  slight  excess  of  metal  on  the  machined 
side  it  can  easily  be  filed  off. 

REPAIRING    A    SCORED    CYLINDER. 

Frequently  a  wrist  pin  works  loose,  with 
the  result  that  the  friction  wears  a  slot 
almost  the  entire  length  of  the  cylinder. 
This  means  loss  of  compression,  and  if  the 
score  is  very  deep,  very  little  power  will 
be  obtained  from  that  cylinder.  To  repair 
this  by  welding  is  not  an  easy  undertak- 
ing. When  the  welding  is  completed,  of 
course  it  is  necessary  to  regrind  the  cyl- 
inder. This  is  not  objectionable,  but  in 
the  majority  of  cases  it  is  necessary  to 
regrind  until  the  cylinder  is  enlarged, 
which  moans  an  oversize  piston  must  bo 
used.  In  addition  to  this  added  expense 


WELDING    CRANK    CASE    ARM  153 

there  are  other  objections,  so  that  we  would 
advise  brazing.  The  cylinder  must  be  pre- 
heated just  as  though  welding  were  to  be 
employed.  Particular  care  should  be  used 
in  cleaning  the  score.  Tobin  or  manganese 
bronze  can  be  employed,  using  a  flux. 
Those  shops  not  equipped  to  do  regrinding 
will  find  this  method  of  repairing  an  ad- 
vantage. A  small  portable  grinder  is  used 
to  remove  the  roughness,  and  it  can  then 
be  finished  with  scrapers. 

WELDING  ARM  OP  AN  ALUMINUM  CRANK  CASE. 


Fig.  30. 

Quite  frequently  the  arm  of  a  case 
breaks.  This  is  comparatively  a  simple 
weld.  There  is  no  necessity  to  take  care 
of  expansion  and  contraction.  It  is  neces- 
sary to  take  care  of  alignment,  and  to  this 
end  a  straight  bar  should  be  bolted  tight  to 


the  other   arm    on 


same 


sid( 


the 


case,  the  broken  arm  resting  on  the  bar  and 


154    OXY-ACETYLENE  WELDING  &  CUTTING. 

being  clamped  to  it,  care  being  taken  that 
the  clamps  are  not  drawn  too  tight.  It  will 
be  best  to  start  welding  along  the  top  first 
and  then  weld  each  side,  finishing  by  weld- 
ing on  the  inside,  where  a  fillet  or  rein- 
forcement can  be  made. 

WELDING   CRACK    IN   ALUMINUM    OIL    PAN. 


Fig.  40. 


Fig.  40  shows  an  aluminum  oil  pan  with 
a  crack,  AB,  lined  up  and  ready  to  weld. 
Angle  irons  are  bolted  to  the  case.  The 
holes  in  the  angle  irons  should  be  some- 
what larger  than  the  holes  in  the  case  and 
the  bolts  should  not  be  drawn  tight  so 
that  the  case  will  have  an  opportunity  to 
expand  when  heated,  but  will  do  so  along 
the  line  and  in  the  direction  of  the  angle 
irons.  The  case  should  be  pre-heated,  either 
with  charcoal,  gas  torch  or  with  the  weld- 
ing torch.  The  heating  should  mainly  bo 
on  the  side  opposite  to  the  crack  AB.  The 


WELDING   A    FLY-WHEEL.  155 

degree  of  heat  is  not  only  somewhat  diffi- 
cult to  determine,  but  is  also  one  regarding 
which  good  welders  differ.  Some  prefer 
to  heat  until  the  metal  begins  to  sweat.  In 
the  majority  of  instances  this  is  not  neces- 
sary, besides  one  is  getting  dangerously 
near  the  point  where  the  case  will  collapse 
and  be  ruined.  Others  take  some  salt  or 
sawdust  and  sprinkle  on  the  case,  and  if  it 
chars  or  burns  quickly,  proceed  to  weld. 
The  welding  should  start  at  A  and  proceed 
towards  B ;  never  in  the  opposite  direction. 
Always  work  a  weld  out  towards  the  edge. 
AVhen  the  weld  is  practically  completed, 
the  one  angle  iron  on  that  side  should  be 
removed  and  the  crack  touched  up,  a  little 
more  metal  being  added  than  necessary. 
This  excess  metal  can  easily  be  filed  off. 

WELDING  OF  A  FLY-WHEEL. 

X 


41. 

Fii>'.  41   represents  a  cast-iron  fly-wheel, 
having  a  break  in  a  spoke  at  A,  and  also 


156    OXY-ACETYLENE  WELDING  &  CUTTING. 

a  break  in  the  rim  at  B.  First,  let  us  as- 
sume that  there  is  only  one  break,  and  it 
is  at  "A."  We  should  have  learned  by 
this  time  that  if  we  attempted  to  make  this 
weld  and  gave  no  thought  as  to  expansion 
and  contraction,  that  it  would  be  sure  to 
break  again  when  cooling.  The  proper  way 
to  take  care  of  expansion  and  contraction 
is  to  heat  the  rim  to  a  dull  red  on  both  sides 
of  this  broken  spoke.  As  the  rim  is  heated 
it  expands  outwardly,  and  it  will  be  seen 
that  the  edges  of  the  break  have  separated. 
The  weld  should  then  be  made  as  rapidly 
as  possible  and  the  wheel  covered  up  care- 
fully and  allowed  to  cool  slowly. 

Now  let  us  suppose  that  we  have  a  bro- 
ken spoke,  A,  and  a  broken  rim,  B.  This 
is  really  more  simple  than  the  one  single 
break  in  the  spoke  at  A,  if  we  go  at  it  in 
the  proper  way.  The  break  at  A  must 
always  be  made  first.  Before  beginning 
the  weld,  two  flat  iron  bars  should  be 
clamped  along  the  sides  of  the  rim  to  main"- 
tain  alignment.  The  weld  at  A  should  be 
started  and  a  heavy  "tack"  made,  then 
turn  the  wheel  over  and  weld  one-half  the 
way  through,  when  the  wheel  should  again 
be  turned,  the  "tack"  melted  out  and  the 
weld  completed.  Upon  examining  the 
crack  in  the  rim  at  B,  in  nil  probability  it 
will  be  seen  that  the  part  of  the  rim,  XB, 


WELDING    CRANK    SHAFT.  157 

extends  a  little  farther  out  than  does  BY. 
This,  of  course,  is  due  to  the  fact  that 
the  spoke  has  expanded  from  the  heat  of 
welding,  so  we  should  carefully  heat  the 
rim  at  Y  until  it  expands  and  the  two  edges 
of  the  crack  at  B  are  even  and  true.  Then 
make  the  weld,  cover  the  casting  and  cool 
slowly. 

WELDING  OP   LARGE   CYLINDERS. 

In  the  pre-heating  of  large  cylinders  usu- 
ally better  results  can  be  obtained  by  chang- 
ing somewhat  the  method  used  on  ordinary 
automobile  cylinders.  The  inner  wall  of 
large  stationary  gas  engine  cylinders  is 
usually  considerably  heavier  than  the  out- 
er or  water  jacket  wall.  The  cylinder 
should  be  well  swabbed  with  graphite  and 
then  stood  upright,  the  lower  end  resting 
on  bricks,  leaving  an  air  space  of  about  3 
or  4  inches  at  the  bottom.  Some  charcoal 
is  then  placed  inside  the  cylinder  and  al- 
lowed to  heat  until  the  outer  wall  is  fairly 
hot.  It  then  should  be  turned  over  on  its 
side  and  heated  all  over. 

If  gas  torches  are  used,  this  is  not  neces- 
sary, as  a  small  one  can  be  placed  so  as 
to  play  on  the  inside,  but  not  against  the 
walls  of  the  cylinder. 

WELDING  A  CRANK   SHAFT. 

The  welding  of  a  crank  shaft  should  not 


158    OXY-ACETYLENE  WELDING  &  CUTTING. 

be  attempted  until  one  has  had  at  least  a 
year's  experience  in  welding.  Automobile 
shafts  are  steel  with  a  fairly  high  carbon 
content,  and,  in  addition,  frequently  con- 
tain nickel,  chrome,  etc.  Good  welders  can 
do  this  class  of  work  successfully ;  the  fair 
or  mediocre  operator  would  do  well  to 
"pass  them  up." 


Fig.  42. 


Regardless  as  to  the  quality  of  the  weld, 
it  will  be  necessary  to  put  the  shaft  in  a 
lathe  and  do  some  straightening,  after  the 
weld  is  completed. 

Now   the   amount  of  work  required   in 


WELDING  TANK  WAGONS.        159 

straightening  can  be  considerable  or  very 
little,  depending  upon  the  care  exercised 
in  lining  np  the  shaft  before  welding,  and 
the  means  for  holding  it  approximately  in 
that  position.  Some  advocate  the  use  of 
"V"  blocks  for  this  purpose.  Besides  be- 
ing quite  expensive,  they  are  of  very  little 
value,  and  a  straight  piece  of  heavy  angle 
iron  will  answer  as  well. 

A  simple  and  inexpensive  means  for 
holding  shafts  is  shown  in  Fig.  42.  It  is 
copied  very  much  after  the  steady  rest  on 
a  lathe.  The  shaft  is  lined  up  by  means  of 
set  screws  arid  a  straight  edge  and  a  sur- 
face gauge  are  used  to  determine  when  it 
is  correct.  The  shaft  is  then  tacked  and 
again  tried  to  see  if  it  is  true  and  the  set 
screws  are  tightened  so  that  the  shaft  can 
be  easily  turned.  The  weld  is  then  made. 

AVhen  finished  and  while  hot,  it  is  again 
tested,  and  if  "off"  it  is  an  easy  matter 
to  straighten  by  tightening  up  on  one  set 
screw  while  loosening  the  opposite  one. 

A  great  many  shafts  have  been  welded 
on  a  device  of  this  kind  and  very  little  ma- 
chining was  necessary  afterwards. 

WELDING  OF  PARTITIONS  IN  OIL  TANK 
WAGONS. 

Most  of  the  oil  concerns  who  deliver 
oil  in  tank  wagons,  when  ordering  new 


160    OXY-ACETYLENE  WELDING  &  CUTTING. 

tanks  are  specifying  that  they  shall  be 
welded  throughout.  These  tanks  carry 
gasoline,  kerosene  and  other  grades  of  oil, 
so  that  this  calls  for  several  compartments, 
necessitating  partitions.  As  a  leak  in  a 
partition  might  result  seriously,  they  usu- 
ally specify  that  there  must  be  provided 
two  partitions,  instead  of  one.  These  par- 
titions are  made  from  flat  stock  and  are 


V 


dished  very  much  like  a  pie  pan.  This  is 
practically  all  that  is  necessary,  to  take 
care  of  expansion  and  contraction.  The 
edges  at  the  ends  of  two  tanks  are  flanged, 
the  two  dished  partitions  are  set  in  posi- 
tion (see  Fig.  43),  and  the  four  edges  are 
tacked  at  four  or  five  points.  The  four 
are'then  welded  all  the  way  around. 


CONSTRUCTION  OF  WELDING  HORSE.      161 
WELDING  HORSE. 

Figure  44  shows  a  welding  horse,  with 
aluminum  case  in  position  being  welded. 
This  horse  is  so  simple  to  make  and  yet  is 
so  great  a  convenience  in  a  custom  repair 
shop,  that  a  description  of  it  and  its  uses 
would  seem  advisable. 

In  the  majority  of  shops  the  custom  has 
been  for  the  welder  to  use  a  helper  when 
working  on  aluminum  cases,  especially  if 
they  were  of  rather  large  size.  The  du- 
ties of  the  helper  were  to  turn  the  casting 
from  time  to  time,  keeping  the  portion  that 
was  actually  being  welded  in  a  horizontal 
position.  Sometimes  the  helper  was  dis- 
pensed with  and  the  welder  did  his  own 
turning,  supporting  the  casting,  from  time 
to  time,  by  means  of  brick  or  other  de- 
vices. At  times  this  places  a  considerable 
strain  on  the  casting,  causing  it  in  some 
instances  to  crack  elsewhere  than  in  the 
weld.  Often  the  supporting  bricks,  hav- 
ing been  placed  hurriedly  in  position, 
would  slip  and  allow  the  case  to  drop,  with 
more  or  less  resulting  damage.  This  weld- 
ing horse  eliminates  all  of  this.  The  case 
is  simply  bolted  to  the  frame  of  the  horse. 
The  frame  and  the  attached  case  can  re- 
volve on  the  supporting  shaft  by  loosening 
a  set  screw  and  can  be  instantly  fixed  in 


162    OXY-ACETYLENE  WELDING  &  CUTTING. 

any  desired  position  by  simply  tightening 
the  set  screw.  This  horse  is  made  as  fol- 
lows : 

The  legs  are  made  of  ordinary  standard 
%"  PiPe  and  are  Cl1^  about  32  inches  long. 
A  piece  of  l^i-inch  pipe  about  six  inches 


Fig.   44. 
Welding1     Horse     for     Holding     Aluminum     Cases. 

long  is  butted  against  two  legs  and  welded. 
The  legs  should  be  positioned  to  incline  in- 
ward somewhat.  On  the  top  of  the  short 
l^-inch  pipe  build  up  a  lug  about  %-inch 
high.  Then  drill  about  a  %-inch  or  %-inch 


DIE   WELDING.  163 

hole  and  tap.  This  is  to  receive  a  set 
screw.  Then  get  tw^o  straight  pieces  of 
angle  iron  about  4  or  5  feet  long.  This 
angle  iron  should  be  about  2"x2"x1/4".  At 
each  end  cut  out  a  small  square  from  one 
flange  about  2"x2". 

This  cut  should  be  made  on  the  same 
flange  for  both  pieces  of  angle  iron.  Weld 
on  the  under  side  of  the  uncut  portion  a 
piece  of  bar  stock  formed  in  a  "U??  shape. 
This  will  form  a  slot  through  which 
passes  a  flat  bar  forming  the  end.  On  the 
side  of  the  "U"  shaped  piece  build  up  a 
lug,  drill  and  tap  for  a  set  screw7. 

For  the  ends,  get  two  pieces  of  flat  stock 
about  li/X/'x1/^"?  and  each  two  feet  long. 
In  the  center  of  each  and  at  right  angle 
weld  a  piece  of  1"  pipe  about  8"  long.  These 
two  pieces  of  pipe  will  form  the  shaft  for 
the  welding  horse  and  the  bearings  will  be 
the  two  pieces  of  l1/^"  pipe  welded  onto  the 
legs.  The  two  pieces  of  angle  iron  which 
form  the  sides  can  be  moved  in  or  out  on 
the  two  flat  bars  forming  the  ends,  and 
thereby  adjusted  to  the  width  of  the  case. 
Ordinary  clamps  are  used  to  fasten  the 
case  to  the  angle  irons. 

WELDING    OP    DIES. 

Dies  are,  of  course,  made  from  high  car- 
bon steel.  As  we  have  previously  stated, 


1  ()4    OX Y- ACETYLENE  WELDING  &  CUTTING. 

high  carbon  steels  are  difficult  to  weld; 
however,  very  satisfactory  welding  is  done 
on  this  class  of  work.  Ordinary  Norway 
iron  can  be  used  as  a  filler,  but  it  must  be 
remembered  that  it  will  be  impossible  to 
temper  the  metal  in  the  weld  on  account 
of  its  low  carbon  content.  Some  concerns, 
notably  shoe  factories,  use  a  great  many 
small  cutting  dies.  They  are  very  thin, 
and  the  breakage  is  considerable.  In  weld- 
ing, Norway  was  used,  but  it  was  exceed- 
ingly difficult  to  prevent  blow-holes  from 
forming  near  and  at  the  thin  cutting  edge. 
By  experimenting,  a  high  carbon  filler  rod 
was  found  which  eliminated  this  trouble 
and  also  gave  a  harder  cutting  edge.  Those 
interested  sufficiently  to  write  to  the  author 
.will  be  gladly  given  the  name  of  this  steel. 

WELDING  OF  HIGH  CARBON  TOOL  STEEL 
TO  LOW  CARBON. 

The  exceedingly  high  price  of  high  car- 
bon steel  during  the  past  year  has  caused 
many  concerns  to  interest  themselves  in 
some  method  that  would  show  an  economy 
in  the  use  of  this  material,  with  the  result 
that  a  great  many  are  now  using  for  their 
cutting  tools  a  small  piece  of  high  carbon 
to  which  has  been  welded  a  longer  piece  of 
low  carbon.  The  same  thing  is  done  with 
high  speed  and  tool  steel.  Very  little,  if 


TOOL  STEEL  WELDING.  165 

any,  bevel  is  made  on  the  high  carbon  piece, 
whereas  a  very  long  bevel  is  made  on  the 
low  carbon  bar.  The  secret  as  to  success- 
ful welding  on  this  class  of  work  is  in  pre- 
heating both  pieces  until  they  are  a  cherry 
red  all  over  and  then  welding  fast,  using 
as  a  filler  either  vanadium  or  nickel  steel, 
although  Norway  can  be  used. 

WELDING    OF    MANGANESE    STEEL. 

The  welding  of  manganese  steel  is  not 
a  success.  While  the  metal  can  be  run  to- 
gether, the  weld  will  be  found  to  be  porous, 
brittle,  and,  of  course,  possessing  little 
strength.  It  is  extremely  doubtful  if  it 
ever  will  be  welded  successfully  with  the 
flame.  The  government  specifications  for 
this  steel  call  for  a  manganese  content  of 
not  less  than  11%  nor  more  than  13%. 
Manganese  has  a  great  affinity  for  oxygen, 
with  the  result  that  when  the  steel  is  melted 
a  considerable  amount  of  the  manganese 
burns  out,  leaving  less  than  11%  behind. 
Attempts  to  put  manganese  back  into  the 
casting  by  using  a  filler  rod  high  in  man- 
ganese have  not  proven  a  success,  as  it 
would  be  luck  if  only  enough  were  added  to 
come  within  the  narrow  range  of  from  11% 
to  13%.  Manganese  steel  is  used  for  switch 
frogs,  safes,  ore  crushing  rolls,  dredge  dip- 
pers, etc. 


\    - 

166    OXY-ACETYLENE  WELDING  &  CUTTING. 
THE  USE  OF  ALUMINUM   SOLDER. 

Those  doing  custom  welding  should  be 
capable  of  soldering  aluminum.  It  is  not 
difficult,  and  there  are  occasions  when  its 
use  is  desirable.  It  must  be  remembered 
that  a  soldered  joint  will  not  have  the 
strength  of  a  weld,  claims  of  some  manu- 
facturers of  aluminum  solder  to  the  con- 
trary notwithstanding.  For  that  reason 
soldering  should  not  be  resorted  to  where 
it  is  necessary  to  secure  in  the  joint 
strength  equal  to  other  parts  of  the  cast- 
ing. A  small  crack  in  the  bottom  of  an 
aluminum  oil  pan  is  an  instance  in  which 
soldering  can  be  successfully  done.  Here 
there  is  no  strain  and  little  strength  re- 
quired. The  important  consideration  is 
that  it  shall  be  oil  tight. 

The  crack  is  beveled  out  to  an  angle  of 
at  least  90  degrees.  It  is  of  the  utmost 
importance  that  it  shall  be  clean  and 
bright.  A  tip  of  small  size  should  be  used 
in  the  welding  torch  and  only  the  brush 
flame  or  envelope  brought  in  contact  with 
the  metal.  While  the  crack  is  being  heated 
a  wire  hand  brush  should  be  used  vigor- 
ously until  the  sides  are  as  bright  as  a 
new  silver  dollar.  Any  good  aluminum 
solder  can  be  used.  There  are  quite  a 
number  on  the  market.  As  soon  as  the 
crack  is  clean  and  fairly  warm,  rub  the 


SOLDERING  ALUMINUM.  167 

end  of  the  solder  in  the  crack  and  on  the 
side  and  a  small  amount  will  adhere.  The 
wire  brush  must  be  then  used  again,  rub- 
bing the  solder  in  until  every  crack,  crevice 
and  part  of  the  beveled  sides  are  coated 
with  the  solder.  While  this  is  being  done 
the  torch  is  being  played  over  the  crack  and 
by  this  time  the  casting  should  be  hot 
enough  to  melt  the  solder  when  it  is  rubbed 
against  the  crack.  Melt  enough  to  fill  up 
the  crack  and  extend  over  the  sides  a  little 
and  use  an  old  hickory  hammer  handle  that 
has  been  flattened  on  one  side  to  press  the 
solder  into  shape.  When  this  has  been 
done,  be  careful  not  to  move  the  casting 
until  it  has  cooled  sufficiently  to  allow  the 
solder  to  set. 

USE  OF  OXYGEN  FOR  REMOVING  CARBON. 

The  use  of  oxygen  for  the  removal  of 
carbon  in  cylinders  is  now  very  generally 
employed.  The  process  is  one  of  simple 
combustion,  the  carbon  burning  to  a  gas 
in  the  presence  of  pure  oxygen.  This  burn- 
ing is  usually  attended  by  a  considerable 
pyrotechnic  effect,  so  that  the  onlooker  is 
apt  to  think  that  an  exceedingly  high  tem- 
perature is  obtained  which  might  injure 
the  cylinder.  Such  is  not  the  case.  The 
temperature  is  somewhat  below  that  pre- 
vailing in  the  combustion  chamber  when 


168    OXY-ACETYLENE  WELDING  &  CUTTING. 


Fig.  45. 

This  cut  shows  a  large  casting  on  an  ice  machine 
that  was  welded.  A  part  of  the  flange  was  broken  off 
and  the  crack  extended  up  into  the  body  of  the  casting. 
It  was  necessary  to  dismantle,  but  presented  no  serious 
difficulty  in  welding  aside  from  the  fact  that  the  turning 
of  a  casting  of  its  size  in  order  to  get  at  every  part 
of  the  crack  was  somewhat  tedious. 

The  entire  end  of  the  casting  was  pre-heated. 


CARBON   CLEANING.  169 

the  engine  is  running  so.  that  no  trouble 
can  come  from  that  score.  An  analysis  of 
the  carbon  in  cylinders  discloses  that  it 
contains  road  dust  or  silica.  The  oxygen 
will  not  remove  this. 


Fig.  46. 

This  cut  shows  a  large  copper  still  with  longitudinal 
seams  and  connections  welded.  This  still  was  4%  feet 
in  diameter  by  about  6  feet  high.  The  metal  did  not 
exceed  ^  of  an  inch  in  thickness,  and  yet  on  account 
of  the  conductivity  of  the  copper  it  was  found  necessary 
to  build  a  coke  fire  on  the  inside  and  cover  the  outside 
with  asbestps  in  order  to  hold  the  heat. 

To  those  not  familiar  with  the  process 
it  is  necessary  to  impress  upon  them  that 
oxygen  only  is  used.  Acetylene  plays  no 
part  and  is  not  used,  the  carbon  in  the 
cylinder  acting  as  the  only  fuel.  The  equip- 


170    OXY-ACETYLENE  WELDING  &  CUTTING. 

meiit  necessary  is  a  tank  of  oxygen,  a  regu- 
lator which  reduces  the  pressure,  about  12 
feet  of  hose  and  either  a  special  carbon 
torch  or  a  special  tip  which  is  attached  to 
the  welding  torch.  The  operation  is  pre- 
pared for  as  follows : 


Fig.  47. 

This'  cut  shows  an  armature  with  shaft  beveled  and 
lined  up  preparatory  to  welding1.  In  this  case  the  weld 
was  far  enough  removed  from  the  armature  as  to  not 
endanger  burning  the  insulation.  Where  the  weld  is 
closer  to  the  armature  it  is  necessary  to  cover  that 
end  with  wet  asbestos.  As  the  weld  progresses,  an 
assistant  can  from  time  to  time  slowly  pour  water  on 
the  asbestos. 

The  gasoline  tank  is  cut  off  and  the 
motor  started  and  allowed  to  run  until  it 
stops  of  its  own  accord.  This  indicates  that 
all  of  the  gasoline  in  the  carburetor  has 
been  used  up,  which  is  one  of  the  things 
desired.  It  is  important  that  no  gasoline 


,CAKBON  CLEANING.  171 

he  allowed  to  remain  in  the  line  from  the 
tank  to  the  carburetor,  and  if  there  is  a 
vacuum  feed,  it  should  be  drained.  Re- 
move either  the  valve  caps  or  the  spark 
plug  on  the  first  cylinder  and  turn  the  en- 
gine over  until  this  cylinder  is  on  compres- 
sion. This  means  that  the  piston  is  at 


Fig.  48. 

This  is  a  large  cast-iron  cylinder  14  feet  in  diameter 
and  weighing-  30,000  pounds.  A  part  of  the  flange  was 
broken  off  and  in  addition  there  were  a  great  many 
blow-holes  in  the  unbroken  part. 

On  account  of  the  size,  and  the  fact  that  the  welding 
was  on  an -edge,  no  attempt  was  made  to  pre-heat.  The 
broken  parts  were  welded  back  and  the  blow-holes  filled 
up.  It  was  impossible  to  prevent  chilling  cf  the  metal 
and  in  facing  off,  an  emery  wheel  was  found  necessary. 

The  welded  casting  has  now  been  in  service  several 
years,  giving  entire  satisfaction. 


172    OXY-ACETYLENE  WELDING  &  CUTTING. 

the  top  of  its  stroke  and  the  valves  closed. 
The  oxygen  tank  should  then  be  opened 
slowly  and  the  regulator  set  at  about  15 
pounds.  Drop  a  lighted  match  into  the 
valve  chamber,  insert  the  copper  tubing 
and  turn  on  the  oxvgen.  If  the  flame  is 


Fig.  49. 

This  shows  the  head  of  a  large  ammonia  compressor 
which  was  badly  broken  and  successfully  welded.  Not 
only  was  it  necessary  to  stand  high  pressure,  but  it 
must  also  be  ammonia  tight  and  any  one  familiar  with 
the  penetrating  quality  of  that  gas  realizes  that  the 
weld  had  to  be  free  from  blow-holes.  The  metal  was 
about  3  inches  thick  and  the  length  of  the  break  36 
inches. 

Fortunately,  with  the  exception  of  about  6  inches,  the 
welding  was  all  in  one  position.  The  crack  was  carefully 
chamfered  and  lined  up  and  then  pre-heated  until  red 
all  over. 


CARBON   GLEANING. 


173 


considerable,  reduce  the  amount  of  oxygen 
pressure. 

If  the  carbon  does  not  seem  to  burn  well 
and  increasing  the  oxygen  pressure  does 
not  help,  inject  just  a  few  drops  of  oil, 
kerosene  or  lubricating. 

Compressed  air  or  a  small  hand  bellows 
should  be  used  to  blow  out  particles  of 
road  dust  or  grit  that  remains,  and  the 
valve  seats  should  be  cleaned  with  a  swab. 


This  shows  a  large  fly-wheel  which  had  all  six  spokes 
broken,  and  which  was  successfully  welded. 

In  this  case  the  entire  wheel,  rim,  hub  and  spokes  was 
pre-heated  and  all  but  a  very  little  welding  was  done 
from  one  side.  In  this  case  it  was  impossible  to  keep 
the  bore  in  the  hub  true,  so  that  the  bore  was  enlarged 
and  a  bushing-  inserted. 


174.. OX  Y- ACETYLENE  WELDING  &  CUTTING. 

The   remaining   cylinders   are   treated   in 
like  manner. 

It  is  good  policy  to  have  near  at  hand 
a  fire  extinguisher,  as  the  proximity  of 
grease  and  oils  to  the  flying  sparks  must 
he  considered. 

COST-CARD. 

Some  kind  of  a  time  or  cost  card  should 
be  kept  where  job  or  repair  welding  is 
done.  By  doing  so  you  will  not  only  have  a 
record  of  the  operation  in  the  event  of  a 
dispute,  but  in  a  very  few  months  you  will 
have  on  file  a  history  of  a  great  many  dif- 
ferent jobs,  which  will  be  found  a  great 
assistance  in  determining  a  price  should 
the  customer  desire  it.  Few  custom  weld- 
ing shops  properly  take  into  account  what 
is  known  as  overhead  expense.  This  in- 
cludes rent,  telephones,  advertising,  post- 
age, bad  accounts,  depreciation  of  equip- 
ment, failure  of  welds,  etc.  At  least  100% 
should  be  added  to  the  actual  labor,  gas 
and  material  cost  to  cover  the  overhead. 
Unless  this  is  done  one  will  not  go  ahead. 

If  the  owner  of  the  shop  does  his  own 
welding,  he  should  charge  this  up  at  the 
same  price  he  would  have  to  pay  did  he 
employ  a  welder. 

A  cost  card  for  repair  welding  is  shown 
on  page  177. 


COST  CARD. 


17f) 


Fig.  51. 

This  is  a  cut  taken  of  a  compartment  oil  tank  used 
on  a  delivery  wagon.  The  manner  in  which  the  partitions 
are  formed  and  welded  in  is  described  elsewhere,  as  is 
also  the  welding  of  the  filling  and  drainage  plugs. 

The  manufacture  of  these  tanks  presents  no  serious 
difficulties. 


170 


Fig.    52. 


This  s  h  o  w  s 
p  a  r  t  of  the 
frame  of  a  large 
Hoe  printing 
press.  This  was 
broken  at  the 
white  line  near 
the  man's  hand. 
The  metal  was 
4x5  In.  A 
pre-heating  torch 
was  directed  on 
the  break  but  in 
snch  a  position 
that  the  main 
casting  instead 
of  the  broken-off 
part  received 
most  of  the  heat. 
The  welding  was 
completed  i  n 
only  a  few  hours 
enabling  the  cus- 
tomer to  print 
his  paper  with- 
out the  loss  of  a 
single  issue. 


RECEIPT  TICKET.  177 


uate          June  1st,  1916  Shop  Ticket  No.  50 

Article  Single  Cylinder 

Kind  of  Weld  5  inch  crack  in  water  jacket 

Pressure  uxy.  Start       1750  Ibs.       in  100  cu.  tt.  tank 
pressure  Oxy.  Finish    1400  Ibs. 
350  Ibs. 

GAS   USED. 

Cu.  Ft.  Oxygen         Used     20     @     2c  $  .40 

Cu.  Ft.  Acetylene     Used     20     @     3c  .60 

LABOR. 

Preparing — Hrs.         Min.  30     @     $  .80  .40 

Welding    —Hrs.         Min.  30     @       1.00  .50 

Finishing— Hrs.     1  Min.  @         .80  .80 

MATERIAL. 
Rods 

— Lbs.  Steel  @ 

I  —Lbs.  Cast  Iron  @         .15  .15 

— Lbs.  Bronze  @  " 

— Lbs.  Aluminum  @ 

Flux 05 

— Lbs.  Charcoal 

Pre-Heating  Torch  y2  Hour  .10 


TOTAL $3.00 

RECEIPT    TICKET. 

Whether  the  broken  easting  is  brought  to 
the  welding  shop  by  a  firm  using  their  own 
dray  ticket  or  by  an  individual,  the  welding 
shop's  own  receipt  ticket  should  be  given. 
It  is  important  that  this  receipt  ticket  have 
printed  at  the  top  the  conditions  under 
which  the  casting  is  accepted.  A  sample 
ticket  is  shown  herewith. 

We  guarantee  our  ordinary  class  of  work,  by  re- 
funding the  amount  paid  for  the  work,  if  it  should 
break  again  in  the  line  of  the  weld  within  30  days 


178    OXY-ACETYLENE  WELDING  &  CUTTING. 

from  date  of  delivery  to  owners,  or  we  will  reweld 
again  free  of  charge,  parts  to  be  submitted  to  us, 
transportation  prepaid  for  our  decision.  If  we  can- 
not succeed  in  making  a  satisfactory  job,  we  do  not 
make  any  charge  for  the  work;  our  responsibility 
ends  here. 

We  are  not  responsible   for  the  parts   left   in   our 
charge  after  30  days. 

We  accept  parts  only  as  being  of  scrap  value,  and 
are  not  responsible  for  delays  of  any  kind. 

All  work  is  received  subject  to  above  conditions  and 
guarantee. 

John  Jones   Welding  Co., 
No.    250  Order    No.    52 

St.    Louis,   January    10,   1916. 
Received  from  Smith  Auto  Company 

2826  Locust  Street 
1   Aluminum    Case 

To  be  done  1/12/16  Price       $15.00 

Taken  out  by  Sam  Johnson 

Date  1/12/16 

These  tickets  should  be  made  in  dupli- 
cate, one  being  given  and  one  retained  by 
the  welding  shop,  and  upon  this  latter  one 
the  customer's  receipt  is  obtained  when  the 
casting  goes  out. 

TABLES  AND  USEFUL  INFORMATION. 

WEIGHTS    OP   VARIOUS    METALS. 

Ave.  weight  Ave.  weight 

of  1  cu.  ft.  of  1  cu.  in. 

in  pounds  in  pounds 

Grey  Iron 450  .2606 

Wrought    Iron 480  .278 

Mercury    849  .491 

Silver    655  .579 

Aluminum 162  .0932 

Cast   Copper 542  .313 

Rolled   Copper 555  .321 

Steel   490  .283 

Tin    459  .265 

Zinc    437.5  .252 


USEFUL  INFORMATION. 


179 


METRIC   AND   ENGLISH    SYSTEMS. 


pound 
inch 
foot 
mile 


1  sq. 

1 


inch 
sq.    foot 
1  cubic  inch 
1  cubic   foot 
1  quart 
1  Kilogram 
1  Millimeter 
1  metre 
1  Kilometer 
1  Sq.  Millimeter 
1  Sq.   Metre 
I   Cn.    Centimeter 
1  Cu.   Metre 
1    Litre 


equivalent 
equivalent 
equivalent 
equivalent 
equivalent 
equivalent 
equivalent 
equivalent 
equivalent 
equivalent 
equivalent 
equivalent 
equivalent 
equivalent 
equivalent 
equivalent 
equivalent 
equivalent 


to         .4536 
to     25.4 
to         .3048 
to       1.6094 
to  645.2 
to         .09291 
to     16.39 

.02832 
1.101 
2.2047 
.0394 
3.2807 
.6213 
.00155 
10.763 

.0610 
35.3105 
61.017 


to 

to 
to 
to 
to 
to 
to 
to 
to 
to 
to 


Kilogra  '•,  -,  s 

Millimeters 

Meters 

Kilometers 

Sq.    Millimeters 

Sq.   Meters 

Cu.   Centimeters 

Cu.  Meters 

Litres 

Pounds 

Inches 

Feet 

Miles 

Sq.    Inch' 

Sq.     Feet 

Cubic   Inch 

Cubic  Feet 

Cubic   Inches 


TABLE  SHOWING  THE  ORDER  OF 


Malleability. 

Gold 

Silver 

Aluminum 

Copper 

Tin 

Lead 

Zinc 

Platinum 

Iron 


Ductility. 

Platinum 

Silver 

Iron 

Copper 

Gold 

Aluminum 

Zinc 

Tin 

Lead 


Tenacity. 

Iron 

Copper 

Aluminum 

Platinum 

Silver 

Zinc 

Gold 

Tin 

Lead 


Infusibility, 
Platinum 
Iron 
Copper 
Gold 
Silver 
Aluminum 
Zinc 
Lead 
*Tin 


To  transform  temperature  readings  from  Centi- 
grade to  Fahrenheit  double  the  centigrade  number, 
diminish  it  by  one-tenth  of  itself  and  add  32.  As  an 
example:  100  degrees  Centigrade  is  equivalent  to 
212  degrees  Fahrenheit.  Doubling  100  gives  us  200, 
deducting  one-tenth  leaves  180  and  adding  32  we  have 
212. 

For  changing  Fahrenheit  into  Centigrade  the  rule 
is,  subtract  32,  increase  the  remainder  by  one-ninth 
of  itself  and  take  one-half. 

To  find  diameter  of  a  circle  multiply  circumfer- 
ence by  .31831. 

To  find  circumference  of  a  circle  multiply  diameter 
by  3.1416. 

To  find  area  of  a  circle  multiply  square  of  diameter 
by  .7854. 


180    OXY-ACETYLENE  WELDING  &  CUTTING. 

To  find  surface  of  a  ball  multiply  square  of  diameter 
by  3.1416. 

To  find  side  of  an  equal  square  multiply  diameter 
by  .8862. 

To  find  cubic  inches  in  a  ball  multiply  cube  of 
diameter  by  .5236, 

Doubling  the  diameter  of  a  pipe  increases  its  ca- 
pacity four  times. 

Double  riveting  is  from  16  to  20  per  cent,  stronger 
than  single. 

A  gallon  of  water  (U.  S.  Standard)  weighs  8V3 
pounds  and  contains  231  cubic  inches. 

A  cubic  foot  of  water  contains  iy2  gallons,  1728 
cubic  inches,  and  weighs  62^  pounds. 

To  sharpen  dull  files  lay  them  in  dilute  sulphuric 
acid  until  they  are  eaten  deep  enough. 

A  horse  power  is  equivalent  to  raising  33,000 
pounds  one  foot  per  minute,  or  550  pounds  one  foot 
per  second. 

To  find  the  pressure  in  pounds  per  square  inch  of 
a  column  of  water,  multiply  the  height  of  the  column 
in  feet  by  .43|. 


A  few  concerns  have  expressed  a  desire 
to  avail  themselves  of  an  opportunity  to 
use  the  limited  space  in  the  back  of  this 
book  for  advertising  purposes. 

The  public  can  be  assured  that  each  and 
every  one  is  thoroughly  reliable  and  re- 
sponsible and  the  attention  of  the  reader 
is  especially  directed  to  them. 


ACETYLENE 


IN  PORTABLE  CYLINDERS 
OF   VARIOUS    CAPACITIES 


Commercial  Acetylene  Welding  Co. 

GENERAL  OFFICE,  80  BROADWAY,  N.  Y. 


ATLANTA  BOSTON 

SAN  FRANCISCO        WASHINGTON,  D.  C. 


CHICAGO 
TORONTO 


GOOD  WELDS 

REQUIRE 

PURE  OXYGEN 


DISTRIBUTED  BY 


AIR  REDUCTION  SALES  CO. 

HIGH  PURITY  QUICK  SERVICE 

ABSOLUTE  SAFETY 

BRANCHES  IN  PRINCIPAL  CITIES 
GENERAL  OFFICES 


120  BROADWAY        ....        NEW  YORK 


BURDETT 

OXYGEN 

and 

HYDROGEN 
GAS 

Uniformly      99%     P*re 


PROMPTLY  SUPPLIED  BY  PLANTS  LOCATED 
IN  THE   PRINCIPAL    INDUSTRIAL    CENTERS. 


Main     Office: 

ST.  JOHN'S  COURT  AT  FULTON  STREET 
CHICA  GO. 

PLANTS: 


CHICAGO 
DETROIT 
CINCINNATI 
LOGANSPORT 
ST.  LOUIS 

DENVER 
SALT  LAKE 
SAN  FRANCISCO 
LOS  ANGELES 
FORT  WORTH 

PHILADELPHIA 
WILMINGTON 
PITTSBURGH 
CHATTANOOGA 
OKLAHOMA  CITY 

The  Largest  Producers  of  the  PUREST  Oxygen 
in  the  World. 


PURE  OXYGEN 

and 

HYDROGEN 

Made  by  the  Electrolytic  Process 


Welding  and  Cutting  Apparatus 
Carbon  Cleaning  Outfits 


A  full  stock  of  welding  equipments  is 
carried.  It  will  pay  you  to  write  for 
prices.  Our  Service  Department  is  at 
your  service. 


LOGANSPORT  OXYGEN  CO. 

LOGANSPORT,  INDIANA 

OHIO  ELECTROLYTIC  OXYGEN  CO. 

CINCINNATI,  OHIO 


in- 


formation of 


working* 
for  a 


S: 


TO  THE  TRADE 

Our  firm  is  the  largest  in  this  country 
manufacturing  flame  welding  and  cut- 
ting apparatus  exclusively. 

In  1913  we  were  given  the  Highest 
Award  and  Gold  Medal  at  the  Me- 
chanic's Fair  held  in  San  Francisco,  and 
again  in  1915  we  were  awarded  the  Gold 
Medal  at  the  Panama-Pacific  Interna- 
tional Exposition.  Buy  the  best  —  it  is 
cheapest  in  the  long  run. 

We  manufacture  complete  lines  for 
jobbers  and  manufacturers  who  do 
not  make  complete  lines.  Let  us  fig- 
ure with  you. 

Henderson-Willis  Welding  &  Cutting  Co. 
2305-7-9  N.  llth  Street 
St.  Louis,  Mo.,  U.  S.  A. 


I    L    L    I 
OXY-ACETYLENE 
APPARATUS 
ELDER 


s 


Manufacturers  of  Scientific 

Welding  Torches 
Cutting  Torches 

Duplex  Welding  and  Gutting  Torches 
Lead-Burning  Torches 

Carbon-Cleaning  Torches 

Oxygen  Regulators 
Acetylene  Reducers 

Pressure  Gauges 

Acetylene  Welding  Generators 
Acetylene  Pressure  Tanks 

Gas  Pre-heating  Torches 

Kerosene  Pre-heating  Torches 
Hand  Trucks  for  Portable  Outfits 
Welding  Rods  of  all  kinds 

Welding  Fluxes  of  all  kinds 
Welding  Goggles 

Write  for  Catalogue 

Henderson- Willis  Welding  &  Cutting  Co. 

2305-7-9  N.  llth  Street 
St.  Louis,  Mo.,  U.  S.  A. 


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The  Welding  Engineer 

IN  YOUR  PLANT  there  is  a  man  who 
needs  timely  and  accurate  information  about  weld- 
ing. He  should  know  what  is  being  done  in  other 
plants  to  reduce  costs  and  increase  efficiency.  No 
matter  what  your  welding  problem  may  be  The 
Welding  Engineer  is  the  best  source  of  information, 
the  best  adviser  you  could  have.  Every  phase  of 
welding,  both  manufacturing  and  repair  problems, 
is  discussed  fully  in  this  valuable  monthly  publica- 
tion. The  best  authorities  in  America  on  the 
subject  of  welding  are  regular  contributors. 

Oxy-Acetylene-Electric-Thermit-Carbo- 
Hydrogen  and  Other  Systems 

Every  process  of  welding  is  discussed  by  The  Welding 
Engineer.  Arc  Welding,  Electric  Butt,  Spot  and  Seam 
Welding,  Oxy-Acetylene,  Carbo-Hydrogen  and  the  Thermit 
System,  in  fact  every  known  process  of  joining  metals  is  dis- 
cussed. Cutting  metals  is  an  important  subject.  Study  The 
Welding  Engineer  and  save  gas  and  time.  Welding  and 
Cutting  are  subjects  somebody  in  your  plant  should  study. 

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The  Welding  Engineer 

Edited  by  L.  B.   Mackenzie 

608  So.  Dearborn  St. 
CHICAGO 


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